Version 1.0 – January 2026
Also available in PDF
The CSIRT Services Framework Metrics document is designed to complement the FIRST CSIRT Services Framework v2.1, a widely adopted reference model that defines the services, functions, and activities commonly performed by Computer Security Incident Response Teams (CSIRTs). The FIRST Framework provides a structured and technology-agnostic description of CSIRT service capabilities, but it does not prescribe how to measure the performance, effectiveness, or operational quality of those services.
This metrics document, created by the FIRST Metrics SIG, fills that gap. Its purpose is to define a practical, structured set of quantitative and qualitative metrics that organisations can use to assess, track, and improve the services described in the FIRST Framework. The metrics do not alter or reinterpret the underlying framework; instead, they build upon it by adding measurable indicators that align directly with each service function. In each case, we have aimed to list metrics that are meaningful, practical, and straightforward to understand.
Because organisations vary widely in mission, maturity, tooling, and resourcing, the metrics in this document are intended to be adaptable rather than prescriptive. Each metric includes a description, type, required data, and suggested measures, but individual organisations may tailor the metrics, adjust thresholds, or select alternative statistical methods as appropriate for their environment.
Used together, the two documents offer a comprehensive approach to understanding, managing, and improving CSIRT operations. The Framework describes what a CSIRT does; the Metrics document supports measuring how effectively those services are being delivered.
Note:
The scope of this release intentionally covers Service Areas through Section 7 of the CSIRT Services Framework; metrics for the remaining Service Areas, Sections 8 and 9, will be completed in a subsequent version of this document.
This initial version of the Metrics for the CSIRT Services Framework reflects current practitioner experience and the varying maturity of CSIRT operations, which may result in differences in depth or presentation across service areas. Future revisions are expected to further normalize structure, terminology, and level of detail based on community feedback and practical use.
To maintain clarity and interoperability, this document follows the same hierarchical structure as the FIRST Framework. Each metric is labelled using the corresponding section numbering (for example, 5.1.1.1 indicates the first metric for function 5.1.1). This cross-referencing makes it possible to use both documents together: the Framework provides the conceptual model, while this metrics document provides the means to evaluate how well that model is being executed in practice. In some cases, we have used x.0.0.x for metrics at the service area, not functional, level.
Note that the high-level section numbering omits Sections 3 and 4. This is by design, to ensure correlation with the CSIRT Services Framework, where Service Area numbering starts at Section 5.
The framework for CSIRT services is based on the relationships of these key elements:
These elements are defined as:
SERVICE AREAS
Service areas group services related to a common aspect. They help to organize the services along a top-level categorization to facilitate understanding and communication.
SERVICES
A service is a set of recognizable, coherent functions oriented towards a specific result. Such results may be expected or required by constituents or on behalf of or for the stakeholder of an entity.
FUNCTIONS
A function is an activity or set of activities aimed at fulfilling the purpose of a particular service.
This document includes an additional element – Metrics – resulting in:
Each defined metric relates specifically to its function in the CSIRT Service Framework.
The following conventions apply throughout this document to promote clarity and consistency across all service areas and metrics:
The template below is used as a standard definition for each metric.
| Metric Attribute | Details |
|---|---|
| Name | This is the exact name of the metric. It should match the name that is in the section heading. |
| Description | Provide a detailed description of the metric. How does it relate to the function? What is the intent? Anything that will clarify how this metric is to be used. |
| Type | See Section 2.5 for detailed descriptions of the metrics types. |
| Data Required | Note the specific data points that will be required to calculate this metric. Each individual data point should be a discrete number from which a clear calculation can be made. |
| Calculation | The formula to be used with the above data points to create the metric. The result should be numeric. |
| Measure | This should be one of {Percentage, Mean, Median, Number, Ratio} |
| Notes | Any additional notes that may provide further clarification on this metric. Often this may include comments on the level of effort required for creating this metric. It may include additional insights into why this metric was included, or how to use it. In some cases, we have included sample target ranges. |
We use four types of metrics, directly based on the NIST Measurement Guide for Information Security. These types help ensure the correct focus for each measurement.
Following is the definition of each:
Implementation measures demonstrate the progress of specific controls. Monitoring implementation may include assessment results, such as a tally of known systems or a binary “yes/no” about which systems have up-to-date patches. Implementation measures look at quantitative outputs and are usually demonstrated in percentages.
Effectiveness measures evaluate how well implementation processes and controls are working and whether they are meeting the desired outcome. An effectiveness assessment can either concentrate on the evidence and results of a quantitative analysis of measures or be applied in a qualitative “yes/no” paradigm.
Efficiency measures examine the timeliness of controls by determining the speed at which they give useful feedback, and how quickly those issues are addressed.
Impact measures articulate the impact of information security on an organisation’s unique mission, goals, and objectives including change quantification on areas such as business value, cost savings, trust scores, etc.
Unless otherwise specified, the metrics in this document do not prescribe the use of a particular statistical method. In cases where no method is indicated, organisations may analyse the resulting values using common approaches such as mean, median, percentile distributions, or other summary statistics that best reflect their operational environment.
Where a specific statistical method is recommended, it should not be viewed as restrictive. Raw values may still be trended over time, and alternative statistical techniques may be applied when they provide clearer insight or greater analytical value.
Note:
Top level numbering now skips to Section 5 to maintain correlation with the CSIRT Services Framework
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Sensor / source availability |
| Description | This metric is designed to help ensure that sensors are appropriately available for generating and reporting security events. Without monitoring availability, it is difficult or impossible to assure that your SIEM has a complete data set, which is critical for monitoring and investigations. |
| Type | Effectiveness |
| Data Required | (N1) Binary indicators of individual sensors’ availability, measured over discrete time intervals, e.g. every 5 minutes This number can be gathered in a variety of manners; try to pick a method that most likely guarantees data is being transmitted appropriately. (N2) Number of reporting intervals (may be user selected) |
| Calculation | (N1) / (N2) * 100 |
| Measure | Percentage |
| Notes | Possible availability targets:
Exclude planned outages per log source type, per criticality. Organisations might have different sensor availability requirements for different periods (like operations peaks, non-working hours). Then a few sensors’ availability metrics can be measured for the same sensor. |
| Metric Attribute | Details |
|---|---|
| Name | Sensor / source criticality definition |
| Description | To manage sensor availability and outage response time, a criticality definition should be defined for each sensor. The criticality levels can be defined in any manner to suit your business (e.g., P1, P2, P3 vs. high, medium, low.) The important idea here is that the criticality labels are applied across the full distribution environment. |
| Type | Implementation |
| Data Required | (N1) Number of sensors (N2) Number of sensors with criticality level defined |
| Calculation | N2 / N1 * 100 |
| Measure | Percentage |
| Notes |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Detection coverage against threat TTPs |
| Description | By measuring detection use case coverage against TTPs of threats you have determined to be relevant in a risk-oriented way, it is possible to measure how well your use cases are performing against those TTPs derived from your threat assessment. |
| Type | Effectiveness |
| Data Required | (N1) Count of TTPs relevant for your organisation (N2) Count of your detection use cases mapped to corresponding TTPs |
| Calculations | N2 / N1 * 100 |
| Measure(s) | Percentage |
| Notes | We recommend using the MITRE ATT&CK framework for your threat assessment. We recommend adding and taking into consideration a criticality definition on the TTP matrix to help analyse where to apply resources. |
| Metric Attribute | Details |
|---|---|
| Name | Instruction coverage against number of detection use cases |
| Description | This is a simple metric to help indicate how well your detection coverage is organized, by counting how many of your detection use cases have instructions for analysts defined. |
| Type | Implementation |
| Data Required | (N1) Number of detection use cases (N2) Number of detection use cases with instructions |
| Calculations | N2 / N1 * 100 |
| Measure | Percentage |
| Notes | Having identifiers for your detection use cases corresponding with identifiers for your instructions will help. |
| Metric Attribute | Details |
|---|---|
| Name | False positive ratios per detection use case |
| Description | The ratios of false positives within detection use cases can help identify those use cases that may benefit from tuning. This metric provides two ratios – one against all verdicts, and one against only true positive verdicts |
| Type | Effectiveness |
| Data Required | For each detection use case: (N0) total number of events (N1) total number of events with True Positive verdict (N2) total number of events with False Positive verdict |
| Calculations | N2 / N0 * 100 This is the percentage of false positives for all detections N2 / N1 * 100 This is the ratio of false positive to true positives |
| Measure | Percentage Ratio |
| Notes |
Metrics: The following metric is defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Quality of contextual data |
| Description | Quality defined by percentage of incorrect information received from the external sources providing contextual information. We measure this by counting the number of errors received for the queries launched. These errors can be due to different causes, for example, source unavailability, allowed query limit exceeded, or detected mistakes. |
| Type | Effectiveness |
| Data Required | (N1) Number of queries for context (N2) Number of errors |
| Calculations | N2 / N1 * 100 |
| Measure | Percentage |
| Notes | Determining incorrectness (number of errors) can be difficult and likely to occur downstream from contextual data use |
Metrics: The following metric is defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Mean manual alert correlation |
| Description | The goal of this metric is to evaluate the efficiency of our alert correlation capabilities, to support efficient event analysis. To measure this, we examine how many alerts require manual correlation for each incident. This indicates the number of correlations that are missed pre-triage. |
| Type | Efficiency |
| Data Required | (N1) Number of alerts manually correlated with each incident (manual duplicates) |
| Calculation | Calculate manual alert correlation level (CL) for each incident as 1 / N1 (pct) Calculate the mean of the CL (mCL). |
| Measure | Mean |
| Notes | Higher mCL is better |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Completeness of qualification documentation for alert triage |
| Description | Each qualification should have documentation explaining the verdict choice. |
| Type | Implementation |
| Data Required | (N1) Number of alerts triaged (N2) Number of alerts with qualification documentation |
| Calculation | N2 / N1 * 100 |
| Measure | Percentage |
| Notes | Will likely need to gather the data required via sampling. |
| Metric Attribute | Details |
|---|---|
| Name | Time to acknowledge alerts and incident reports |
| Description | Consistent reaction times to alerts within risk appetite is an indicator to investigate how well the analysts doing the job are equipped and staffed to handle the job expected of them by the organisation. Also, alerts urgency can be a significant factor in the success of your mission. |
| Type | Implementation |
| Data Required | (T1) Time at which the alert report is raised (T2) Time at which the report is acknowledged and analysis is started, either by human or machine |
| Calculation | T2 - T1 (time to acknowledge) |
| Measure | Number |
| Notes | It is highly recommended to have timings of alert creation and acknowledgement recording by machine or system. You will want to analyse the collection of Time to Acknowledge values across a time slice. You may want to analyse per alert type, analyst, or another attribute. |
| Metric Attribute | Details |
|---|---|
| Name | Ratio of true-positives to false-positives |
| Description | Measured at the closure of the alerts, True-positives versus False-positives ratio |
| Type | Effectiveness |
| Data Required | (N1) Count of true-positive alerts (N2) Count of false-positive alert |
| Calculation | N1 / N2 |
| Measure | Ratio |
| Notes | The higher ratio is the more effective ("producing a result that is wanted") detection rules are inspired by reading Threat detection metrics: exploring the true-positive spectrum - by Alex Teixeira. One noted difficulty is ensuring that we have a clear definition and timely marking of what is false-positive and true-positive. |
| Metric Attribute | Details |
|---|---|
| Name | Time to detect |
| Description | Indicates how fast incident detection toolset generates alert or incident from processed log sources |
| Type | Efficiency |
| Data Required | (N1) The time at which the event itself first occurred (N2) The time at which the event was detected |
| Calculation | N2 - N1 |
| Measure | Number |
| Notes | Evaluate this metric to generate statistical analyses over time and type. Note that not all log sources are consolidated instantly, but rather a pulling method is used, focusing on such a metric requires understanding the impact of more frequent polling. Refer to Security Incident Timing Metrics on the FIRST Portal. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Time to acknowledge incident report receipt |
| Description | Measuring reaction times to incident reports can be used to investigate how well the analysts doing the job are equipped and staffed to handle the job expected of them by the organisation. Also, for some alerts urgency can be a significant factor in the success of your mission. |
| Type | Efficiency |
| Data Required | (N1) Time at which the initial incident report received (N2) Time at which acknowledgement of that receipt was sent |
| Calculation | N2 - N1 |
| Measure | Number |
| Notes | Evaluate this metric to generate statistical analyses such as median over time and type of incident. |
| Metric Attribute | Details |
|---|---|
| Name | Percentage of Reports that are Acknowledged |
| Description | This is an easy metric to track report acknowledgement, ensuring processes can be evaluated to avoid having reports fall through the cracks. |
| Type | Effectiveness |
| Data Required | (N1) Number of reports (N2) Number of reports acknowledged |
| Calculation | N2 / N1 * 100 |
| Measure | Percentage |
| Notes |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Time from incident receipt to triage completion |
| Description | This metric can be used to track the amount of time involved in triage activities. By tracking triage durations you can spot trends, compare entities, and analyse your data for efficiency improvements. We caution against setting targets for triage completion due to the risk of negative impact on quality. |
| Type | Effectiveness |
| Data Required | (N1) The point in time when the security event is available for triage (N2) The point in time when the triage is completed |
| Calculation | N2 - N1 |
| Measure | Number |
| Notes | This metric will be most useful when analysed across a variety of attributes such as event report source or analyst team. You can also use receipt acknowledgement as the starting point for this metric if it is more appropriate for your organisation. Refer to Security Incident Timing Metrics on the FIRST Portal |
| Metric Attribute | Details |
|---|---|
| Name | Percentage of quality issues in triage instances |
| Description | Like section 5.2.2, this function includes triaging activity during which verdict, categorization, and prioritization may be assigned. Use this metric to evaluate the quality of this function’s output, with the intent of improving functional processes as needed. |
| Type | Implementation |
| Data Required | (N1) Number of potential security incidents evaluated (N2) Number of errors in triage processing |
| Calculation | (N2 / N1) * 100 |
| Measure | Percentage |
| Notes | Shows quality - if the rate is above the set target threshold determine improvement needed, e.g. additional triage training or improved automation. For simplicity this metrics groups multiple attributes into quality issues. Group or ungroup attributes according to your preference. “Errors” and “Reported Deficiencies” are alternate terms for quality issues. |
Metrics: The following metrics are defined for this function:
Note:
Section 6.2.1 implies that an initial assessment of an information security incident might already be included in a previous step. The information may have been provided to the CSIRT via one of the following channels:
In the above case, qualification has already been accomplished and metrics from those sections may have already been applied.
If the initial assessment has not been completed, then perform the qualification and apply the metrics 5.2.2.1-4 and 6.2.1.1-2 (where it makes sense).
We have added metrics 6.2.1.1-2 as specific to this section.
| Metric Attribute | Details |
|---|---|
| Name | Error rate of incident triage |
| Description | Ensure that incidents have been triaged according to the Security Incident Response Policy to improve the quality of the incident triage. |
| Type | Effectiveness |
| Data Required | (N1) The number of information security incidents where triage has been performed. (N2) The number of information security incidents for which a subject matter expert review revealed triage was not done correctly according to policy. |
| Calculation | (N2) / (N1) * 100 |
| Measure | Percentage (lower is better) |
| Notes | This metric expects that there is a process in which a subject matter expert reviews security incidents to validate the effectiveness of incident triage regarding categorization. This may not always be the case. Risk and compliance environments vary in organisations. You should define what areas of the triage attributes that matters most to you, make it part of your SME review process and consider collecting data for each one to have a more granular understanding of what parts of your triage function are more prone to errors. Example: An expert review process collecting data on categorisation and initial prioritization could reveal that triage fails half the time and it is always the initial prioritization and never the categorization that fails, pinpointing where you should put your effort. |
| Metric Attribute | Details |
|---|---|
| Name | Incidents with altered priority |
| Description | Number of Security Incidents that have their prioritization changed in their lifecycle |
| Type | Efficiency |
| Data Required | (N1) Number of security incidents with altered priority |
| Calculation | N1 |
| Measure | Number |
| Notes | It may be difficult to have an accurate history of how many times the priority for an incident may have changed. Although changes to an incident’s priority during its lifecycle are a valid activity, by analysing the incidents whose priority changed, a team can dig deeper into why this is happening. For example, additional data during triage may help analysts set the priority correctly. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Accuracy of information data sources |
| Description | Assess the reliability and accuracy of information sources providing data and details regarding the security incident. |
| Type | Effectiveness |
| Data Required | (N1) Number of data sources and stores used in your incident (N2) Number of data sources and stores where data accuracy has been validated |
| Calculation | N2 / N1 * 100 (percentage) |
| Measure | Percentage |
| Notes | It may be difficult to reliably validate data accuracy. Accuracy of information data sources will need to be measured through validation processes or other feedback mechanisms. You may need to use sampling for measurements. |
| Metric Attribute | Details |
|---|---|
| Name | Chain of custody compliance |
| Description | Track the completeness of authenticity and integrity controls for data sources used in your security operation, as they adhere to chain of custody compliance restrictions |
| Type | Effectiveness |
| Data Required | (N1) Number of the data sources and stores used in your incident (N2) Number of data sources and stores where sufficient controls are in place to protect the compliance integrity of the data. |
| Calculation | N2 / N1 * 100 (percentage) |
| Measure | Percentage |
| Notes | You will need to define a baseline for what integrity controls are required for your operation and assess your data sources against integrity control baseline. You can increase maturity by checking with your local authorities if your integrity controls would be sufficient for the data to be used in evidence in court. Reference for more details on chain of custody: https://www.cisa.gov/sites/default/files/publications/cisa-insights_chain-of-custody-and-ci-systems_508.pdf |
| Metric Attribute | Details |
|---|---|
| Name | Completeness of contextual data |
| Description | This metric will help you have an overview of the amount of incident data your team collected and attached to incidents. |
| Type | Effectiveness |
| Data Required | (N1) Total number of incidents (N2) Total number of incidents with contextual data attached |
| Calculation | N2 / N1 * 100 |
| Measure | Percentage |
| Notes | This metric does not necessarily address the quality of your contextual data, but rather its presence. If observables are referenced in the incident, they should be included with the case. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Unresolved tasks at incident closure |
| Description | Used as an indicator of potential process failure - where tasks are not being completed by the responsible party. |
| Type | Effectiveness |
| Data Required | (N1) Number of tasks attached to the incident (N2) Number of unresolved tasks at incident closure |
| Calculation | (N2 / N1) * 100 |
| Measure | Percentage |
| Notes | As this metric does not assess the quality of the resolution on tasks, guard against tasks that are resolved simply for the sake of this metric. Consider a QC process using sampling for quality review. |
| Metric Attribute | Details |
|---|---|
| Name | Time to complete tasks |
| Description | Resolution time is a critical component of incident response. Therefore, tasks assigned to incidents should be completed as quickly as possible to avoid negative impact from the incident. Use this metric to assess timeliness. |
| Type | Efficiency |
| Data Required | For each task (t): (N1) Task creation time (N2) Task completion time |
| Calculation | Median({t(N2-N1)} ) |
| Measure | Median |
| Notes | Timing data should be generated (automatically) from system timestamps. Mean can be used but your time series will not likely be a normal distribution resulting in outlier impact. Using median may require stakeholder training. Can be paired with percentiles for clarification. As with 6.2.3.1, this metric does not assess the quality of the resolution on tasks. Guard against tasks that are resolved simply for the sake of this metric. Consider a QC process using sampling for quality review. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Time to complete root cause analysis |
| Description | This metric is used to evaluate time involved in finding the root cause for an incident. By establishing targets or high / low ranges, this metric can be used as a starting point for conducting process analysis to find potential improvements. |
| Type | Efficiency |
| Data Required | (N1) Time at which root cause analysis begins (N2) Time at which root cause analysis is successfully completed |
| Calculation | N2 - N1 |
| Measure | Number |
| Notes | Both the start and end time may be somewhat nebulous but try not to get too caught up in getting the exact moment. The intent of this metric is to help you evaluate efficiency within the process itself. Because this metric is intended to evaluate and drive efficiency, it should not be used as a KPI. You will likely want to analyse the trend in categorised incidents over a period as single numbers will be of limited use except when they fall outside established targets. It is also possible to analyse the set using statistical methods, e.g., median. Refer to section 4.3.4 |
| Metric Attribute | Details |
|---|---|
| Name | Incidents with root cause not identified |
| Description | This metric is designed to help ensure that the root cause of an incident is identified whenever required, thereby helping to reduce the likelihood of future incidents via that same threat vector. |
| Type | Effectiveness |
| Data Required | (N1) - total number of incidents (N2) - number of incidents with root cause not identified |
| Calculation | (N2) / (N1) * 100 |
| Measure | Percentage |
| Notes | Low percentage is better. Root cause analysis can show how much a CSIRT understands the environment tech stack and the teams responsible for, once, in some cases, will be difficult for a CSIRT to perform this function thoroughly, but will need to know who can support. This metric does not measure successful root cause resolution as that may often be out of scope for CSIRTs. |
| Metric Attribute | Details |
|---|---|
| Name | Root cause category analysis |
| Description | Count incident root causes according to their categorization. The intent of this metric is to identify broad areas of impact for attention, e.g. prioritisation, funding, or process improvement. |
| Type | Impact |
| Data Required | (N1) - total number of incidents with root cause category assigned (regardless of value) (N2) - count of incidents per associated root cause category (repeated for each category…) |
| Calculation | N2 / N1 * 100 Repeated for each category |
| Measure | Percentage |
| Notes | Identifying root cause in general can be a resource intensive process. We recommend automating this as much as possible starting with your detection use case management (Section 5.1.2). Examples of root cause category may include phishing, unpatched vulnerability, password hygiene, etc. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Incidents correlated to other incidents |
| Description | The metric can be used to evaluate successful use of cross-incident linking via correlation. |
| Type | Implementation |
| Data Required | (N1) - total number of incidents handled (N2) - number of incidents linked to other incidents via correlation |
| Calculation | N2 / N1 * 100 |
| Measure | Percentage |
| Notes | There may be some difficulty in incident correlation but if that is set up properly this metric should be easy to implement. A relatively large percentage may demonstrate effectiveness in correlating incidents. However, if correlation is set up properly a low value may indicate that most incidents are not related. This is not a qualitative metric, so the value in this metric will be to analyse trending over time, ensuring incident correlation activity is occurring as expected. |
| Metric Attribute | Details |
|---|---|
| Name | Incidents with incorrect correlation |
| Description | In some cases, linkage between incidents might be caused due to error in correlation - understood when looking at the linked incidents. This metric should be used only when there is a substantial number/percentage of the linkage via correlation - to detect the quality of the correlations and if needed to initiate changes in the correlation engine. |
| Type | Effectiveness |
| Data Required | (N1) - Number of incidents correlated to other incidents (N2) - Number of incidents correlated to other incidents, with an incorrect correlation |
| Calculation | (N2) / (N1)*100% |
| Measure | Percentage |
| Notes | N2 can be understood only when the incident correlation is analysed manually (or by AI) so may be difficult to measure. It may need to be accomplished via sample analysis. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Ratio of identified malicious artefacts to total artefacts |
| Description | This metric identifies the ratio of malicious artefacts to the total number of artefacts discovered after media or surface analysis by the incident response team. |
| Type | Implementation |
| Data Required | (N1) Number of total artefacts analysed (N2) Number of malicious artefacts identified |
| Calculation | N2 / N1 |
| Measure | Ratio |
| Notes | A system for storing historical media/surface analysis data is required. This data stored can be the totals themselves or better, a list of all artefacts with associated conclusions that can be summarized. A low number for this metric may show wide collection but relatively few are malicious, impacting workload. A high number may indicate strong pre-filtering but also the risk of missing non-obvious artefacts. Time trending can provide additional insights into process changes The raw numbers of malicious artefacts (N2) can also be useful for trending analysis reflecting a potential need for capacity planning regarding people, infrastructure, or process improvements. |
| Metric Attribute | Details |
|---|---|
| Name | Ratio of artefacts with inconclusive analysis to total artefacts |
| Description | This metric identifies the ratio of inconclusive artefacts to the total number of artefacts using the number of artefacts whose verdict is inconclusive following media or surface analysis by the incident response team. |
| Type | Implementation |
| Data Required | (N1) Number of total artefacts analysed (N2) (N2) Number of inconclusive artefacts |
| Calculation | N2 / N1 |
| Measure | Ratio |
| Notes | A system for storing historical media/surface analysis data is required. This data stored can be the totals themselves or better, a list of all artefacts with associated conclusions that can be summarized. A low number for this metric might give indication of process inefficiencies or errors, yielding inconclusive results. A high number may indicate that the team is not gathering enough artefacts for analysis and may be missing potential threats, indicating potential training or tooling gaps. Time trending can provide additional insights into process changes. The raw numbers of inconclusive artefacts (N2) can also be useful for trending analysis reflecting a potential need for additional training or process improvements. |
| Metric Attribute | Details |
|---|---|
| Name | Number of never seen artefacts |
| Description | This metric tracks the number of artefacts identified by your analysis process that are not found in any known feed. This number can be an indicator of how effective your team is at finding new things, or whether your team is subject to targeted attacks. It is also useful for validating artefact integrity and provenance. |
| Type | Impact |
| Data Required | (N1) Number of artefacts not found in any known repository |
| Calculation | N1 |
| Measure | Number |
| Notes | Use of this metric assumes your team is effective at searching known indicators, whether in public or private repository. The inverse of this metric could be listed as “Hash Verification Success Rate”. Either number will suffice - number not found, or number found. |
6.3.1.4 Time to identify key artefact attributes
| Metric Attribute | Details |
|---|---|
| Name | Time to Identify Key artefact Attributes |
| Description | Measures the time taken to identify critical artefact attributes such as file types or cryptographic hashes. This can indicate efficiency improvements or bottlenecks |
| Type | Efficiency |
| Data Required | For each analysis a (N1) Start time of analysis (N2) Time at which key attributes are identified and the analysis is complete |
| Calculation | median({a(N2-N1)} ) |
| Measure | median |
| Notes | Your team will benefit from analysing the median trend over a period, e.g., quarterly. As with all time metrics be careful using this as a performance metric thereby potentially sacrificing quality to reach a target. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Number of reversed engineered suspicious artefacts |
| Description | Count how many suspicious artefacts were reversed engineered during a time frame, ensuring completeness and throughput of the service in an organisation. |
| Type | Implementation |
| Data Required | (N1) Number of reversed engineered suspicious artefacts |
| Calculation | N1 |
| Measure | Number |
| Notes | A platform to track and maintain historical data of reverse engineering processes is required. This metric can be captured as a raw number over a period or averaged over a period of time and/or other factors. |
| Metric Attribute | Details |
|---|---|
| Name | Number of IOCs collected during reverse engineering |
| Description | Count how many IOCs were discovered during reverse engineering during a specific timeframe, including all techniques. (dynamic, static, decompilation, etc.) |
| Type | Impact |
| Data Required | (N1) Number of IOCs collected as result of reverse engineering |
| Calculation | N1 |
| Measure | Number |
| Notes | A platform to track and maintain historical data of reverse engineering processes is required. To effectively track and utilize the Number of IOCs collected during reverse engineering, it is essential to establish a clear and standardized definition of an IOC. This ensures consistency and enhances the reliability of this metric. Examples of IOCs include IP addresses, domains, registry keys, hashes, Mutex names, Process names, Network artefacts, Email address and Malware behaviour patterns. This metric can be captured as a raw number over a period, or averaged over a period and/or other factors. |
| Metric Attribute | Details |
|---|---|
| Name | Time to complete reverse engineering |
| Description | Measures the time elapsed from the start of the reverse engineering process to its completion, for an individual artefact. |
| Type | Efficiency |
| Data Required | (N1) Time at which reverse engineering process started (N2) Time at which reverse engineering process completed |
| Calculation | N2 - N1 |
| Measure | Number |
| Notes | A platform to track and maintain historical data of reverse engineering processes is required. Evaluate this metric to generate statistical analyses over time and type, such as median. This metric does not necessarily capture effort required for the reverse engineering process. |
| Metric Attribute | Details |
|---|---|
| Name | Effort to complete reverse engineering analysis |
| Description | Measures the amount of effort required to reverse engineer an individual artefact. |
| Type | Implementation |
| Data Required | (N1) Effort required to reverse engineer an artefact |
| Calculation | N1 |
| Measure | Number |
| Notes | It may be difficult to estimate the effort needed to complete the reverse engineering activities and likewise difficult for the reverse engineering team to keep track of their effort expenditure. Keep these activities as simple as possible so as to not add unnecessary overhead. One method to consider is to use a point system that creates a rough estimate of the activities. (Agile story pointing provides a methodology for this. Reference this Asana blog post.) |
The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Number of artefacts analysed during dynamic analysis |
| Description | This is a simple metric to keep track of the number of artefacts that are analysed. It can be used in trending to keep track of how the team is operating, as well as in other metrics for successful analysis and new IOCs identified. |
| Type | Impact |
| Data Required | (N1) Number of artefacts were analysed during dynamic analysis |
| Calculation | N1 |
| Measure | Number |
| Notes | You will need a proper platform to keep track of the artefacts that are analysed during the dynamic analysis process |
| Metric Attribute | Details |
|---|---|
| Name | Number of IOCs identified during dynamic analysis |
| Description | Tracks the total number of IOCs observed through dynamic analysis, regardless of whether they are new or previously known. This provides a sense of the volume and breadth of indicators generated by this analysis function. |
| Type | Impact |
| Data Required | (N1) Number of IOCs identified during dynamic analysis |
| Calculation | N1 |
| Measure | Number |
| Notes | You will need a method for extracting and recording IOCs from dynamic analysis sessions, such as from sandbox reports or network capture logs. This metric helps show the observable footprint of suspicious artefacts when executed. It may include URLs, IPs, domains, file hashes, mutexes, and more. |
| Metric Attribute | Details |
|---|---|
| Name | Number of new IOCs identified during dynamic analysis |
| Description | Tracks the number of previously unknown IOCs discovered during dynamic analysis. This helps measure the uniqueness and added value of the analysis to the organisation’s threat intelligence. |
| Type | Impact |
| Data Required | (N1) Number of IOCs identified during dynamic analysis that were not already present in internal or shared threat intelligence sources. |
| Calculation | N1 |
| Measure | Number |
| Notes | This metric requires comparison of extracted IOCs against an up-to-date IOC repository to confirm novelty. Matching may need to account for IOC type and normalization (e.g., domain variations). You will need a proper platform to keep track of the suspicious IOCs that are analysed during the dynamic analysis process |
| Metric Attribute | Details |
|---|---|
| Name | Percentage of artefacts requiring re-analysis |
| Description | Measures the percentage of artefacts that require re-analysis after the initial runtime analysis, indicating the thoroughness of the first analysis or the need for further investigation. |
| Type | Efficiency |
| Data Required | (N1) Total number of artefacts analysed (N2) Number of artefacts that required re-analysis |
| Calculation | (N2 / (N1) *100 |
| Measure | Percentage |
| Notes | Identifying when a re-analysis is necessary; may require thorough record-keeping and review of analysis logs. A higher percentage of re-analysis may indicate a need for improved initial analysis processes or more effective tools. |
| Metric Attribute | Details |
|---|---|
| Name | Incidents where runtime analysis informed containment or mitigation |
| Description | Tracks how often runtime analysis directly contributes to informing containment or mitigation strategies for incidents. This metric ties the value of dynamic analysis to actual incident response efforts. |
| Type | Effectiveness |
| Data Required | (N1) Number of incidents where runtime analysis informed containment or mitigation |
| Calculation | N1 |
| Measure | Number |
| Notes | Requires detailed documentation linking dynamic analysis results to specific incident containment or mitigation actions. Demonstrates the real-world impact of runtime analysis in reducing threat impact through proactive response strategies. |
The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Number of artefacts correlated per threat actor |
| Description | How many artefacts were correlated per threat actor. This metric can show how many correlations were done by artefact correlation analysis, more is better. |
| Type | Efficiency |
| Data Required | N1 = Number of artefacts |
| Calculation | N1 |
| Measure | Number |
| Notes | You will need a repo of artefacts and tools to compare historically or "retro-hunting" against known and new threat actors. |
| Metric Attribute | Details |
|---|---|
| Name | Number of IOCs correlated per threat actor |
| Description | A count of the IOCs that are associated with a specific threat actor. |
| Type | Efficiency |
| Data Required | (N1) Number of IOC per threat actor |
| Calculation | N1 |
| Measure | Number |
| Notes | You will need a repo of artefacts and toolings to compare historically or "retro-hunting" against known and new threat actors. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Incidents meeting successful resolution criteria |
| Description | This metric provides insight into the efficiency and effectiveness of the Incident Response Plan by measuring the total number of incidents that have been successfully resolved within a given period. It helps organisations evaluate their ability to handle disruptions and restore normal operations, contributing to overall service quality and customer satisfaction. The criteria for successful resolution should be defined in the response plan. (See notes) |
| Type | Effectiveness |
| Data Required | (N1) Number of Incidents Resolved (N2) Incidents Meeting All Resolution Criteria as defined by response plan |
| Calculation | (N2) / (N1) * 100 |
| Measure | Percentage |
| Notes | Data Accuracy: Ensuring the accuracy of incident data and feedback Defining Resolution Criteria: Establishing clear and consistent criteria for what constitutes a successfully resolved incident An incident may be considered successfully resolved when it meets predefined criteria such as issue closure, customer satisfaction, compliance with service level agreements (SLAs), and confirmation from the reporters that the issue is resolved. Possible Resolution Criteria:
|
| Metric Attribute | Details |
|---|---|
| Name | Revenue loss due to security incidents |
| Description | Measure the total revenue loss caused by security incidents over a specific period. This metric evaluates the financial and operational impact of security breaches, highlighting how incidents affect business continuity and profitability. The lower the revenue loss, the more effective the incident response and recovery processes. |
| Type | Impact |
| Data Required | Downtime measure: Identify Affected Systems/Services: Determine which systems or services were impacted by the incident.
|
| Calculation | Calculate Total Downtime: Add up the duration for all affected systems/services to get the total downtime for the incident: Estimate Lost Revenue: Multiply the total downtime by the average revenue lost per hour or day: |
| Measure | Number |
| Notes | Note: This metric is significantly complicated to derive as evidenced with the data accuracy barriers listed below. We have included here as a starting point for those organisations interested in calculating financial impact. Data Accuracy: Ensuring the accuracy of incident data and feedback. It follows some barriers:
Account for Indirect Costs:
Lost revenue example: If your business normally generates $10,000 per hour, and a security incident caused a system outage for 3 hours, with a 50% reduction in operational capacity, the revenue loss would be calculated as: You may want to compare your total revenue loss over a period against an “expected loss” baseline for similar organisations. |
Metrics: The following metric is defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Time to contain |
| Description | Measures the efficacy of containing a detected threat or security incident |
| Type | Efficiency |
| Data Required | (N1) The time at which the event was detected (N2) The time of the incident was contained |
| Calculation | N2 - N1 |
| Measure | Number |
| Notes | Either a ticketing system adept at accurately recording such data or manual log analysis is necessary to assess the timing of the event occurrence. Some corner cases are hard to identify when a threat is contained, sometimes multiples containing phases happen inside the same incident. Refer to Security Incident Timing Metrics on the FIRST Portal This measurement usually spans minutes, hours, or days, contingent upon the complexity and severity of the incident. Gathering data for this metric involves timestamping the instant when containment measures are successfully implemented and validated. This timestamp can be extracted from incident tracking systems, security logs, or documented evidence of containment efforts. It is recommended the logs are aligned with the same time zone. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Median time of resolution |
| Description | The metric measures the time between the onset of the incident and the point at which systems and services are restored to full functionality and capacity. |
| Type | Efficiency |
| Data Required | For each incident a: (N1) Incident start time (N2) Time at which systems and services are restored |
| Calculation | median({a(N2-N1)}) |
| Measure | Median |
| Notes | It may be difficult to know the exact time at which services are restored, and restored to “full” functionality and capacity, but it is an important point to capture. As with other data points that are difficult to determine, use a common-sense approach and keep the determination as simple as possible. Refer to Security Incident Timing Metrics created by the FIRST Metrics SIG for more information. |
| Metric Attribute | Details |
|---|---|
| Name | Effectiveness of incident response in security posture improvement |
| Description | This metric tracks the number of security incidents that resulted in actionable steps (e.g., corrective, preventive, and improvement actions) aimed at strengthening the organisation's security posture. High effectiveness indicates that more incidents are thoroughly investigated, and action plans are created to prevent future occurrences. |
| Type | Effectiveness |
| Data Required | (N1) Incident Count: Total number of incidents over a period (N2) Actionable Incidents: Incidents that resulted in a formalized action plan (e.g., process change, new controls, system patches). |
| Calculation | (N2 / N1) * 100 |
| Measure | Percentage |
| Notes | How this metric can be Interpreted:
Example: If you had 100 incidents and 80 of them generated action plans: E = 80 / 100 * 100 E = 80% An 80% effectiveness rate suggests that the incident response process is well-aligned with security improvement goals. |
| Metric Attribute | Details |
|---|---|
| Name | Percentage of actionable measures successfully implemented |
| Description | Recognizing that successful follow-up on recommended security measures and recommendations may be a lengthy process with much work outside the scope of the CSIRT, this metric tracks how well action plans are implemented. |
| Type | Impact |
| Data Required | (N1) Number of recommended security measures (N2) Number of recommended security measures successfully closed |
| Calculation | N2 / N1 * 100 |
| Measure | Percentage |
| Notes | As mentioned in the description, the CSIRT will often not have control over how many measures are successfully implemented. Therefore, the metric should not be used as a performance indicator. Instead, it should be used as an indicator of the broad impact of the security program and partnerships. |
Metrics: The following metrics are defined for this function:
Metrics: The following metric is defined for this Service:
| Metric Attribute | Details |
|---|---|
| Name | Effectiveness of incident coordination stakeholder survey |
| Description | This metric aims to quantify timeliness, relevance and clarity of coordination communication and quality of the corresponding incident report for incidents with severity X and above. Please see the notes and detailed metric descriptions for full details. |
| Type | Effectiveness |
| Data Required | Ask relevant stakeholders to rate their response from 1 to 5 (5 being best, consider including N/A as an option) Q1 How would you rate how relevant the information shared was to you? (6.5.3) Q2 How would you rate the ability of the CSIRT to coordinate and maintain situational awareness during the incident? (6.5.4) Q3 Was the information regarding current activities delivered in a timely fashion? (6.5.5) Q4 How would you rate the overall quality of the finished incident report? (6.5.5) |
| Calculation | You can use the metrics as is, or do an average, or a weighted average if some metrics are more important to you than others. |
| Measure | n/a |
| Notes | If your organisation does not have an approved survey platform, then consideration should be made to find one that suits your needs regarding confidentiality and security in general. This metric covers the functions 6.5.3, 6.5.4, 6.5.5. You can expand the survey method to other areas of your incident coordination service. |
Metrics: The following metric is defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Communication channel downtime |
| Description | This metric measures the time elapsed since the last received communication. If this duration exceeds expected or normal thresholds, it may indicate a potential issue with your communication channel. Use this metric to help decide when to test whether the channel is still functioning properly. |
| Type | Effectiveness |
| Data Required | (N1) Time of last message in communication channel (N2) Current time |
| Calculation | N2 - N1 |
| Measure | Number |
| Notes | This metric can be repeated for internal and external communication channels if needed. |
Metrics: The following metrics are defined for this function:
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Relevance of notification to recipients |
| Description | This metric aims to measure the relevance of the notification to the recipients by surveying them. |
| Type | Effectiveness |
| Data Required | (N1) The answer to survey question #1; a set of numbers between 1 and 5 from surveyed entities |
| Calculation | N1 |
| Measure | Number |
| Notes | This metric is designed to be bundled with other survey results from 6.5a. |
The following metric is defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Effectiveness of incident coordination and situational awareness development |
| Description | This metric aims to measure the ability of the CSIRT to do incident coordination and create situational awareness, as observed by incident participants. |
| Type | Effectiveness |
| Data Required | (N1) The answer to survey question Q2; A number between 1 and 5 from surveyed entities (or N/A) |
| Calculation | N1 |
| Measure | Number |
| Notes | This metric is designed to be bundled with other survey results from 6.5a. |
The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Stakeholder satisfaction level for timeliness of information |
| Description | This metric aims to measure the ability of the CSIRT to provide timely reports on situational awareness regarding progress |
| Type | Effectiveness |
| Data Required | (N1) The answer to survey question Q3; A number between 1 and 5 from surveyed entities (or N/A) |
| Calculation | N1 |
| Measure | Number |
| Notes | This metric is designed to be bundled with other survey results from 6.5a. |
| Metric Attribute | Details |
|---|---|
| Name | Stakeholder satisfaction level for incident report |
| Description | This metric aims to measure the ability of the CSIRT to create incident reports that are understood by stakeholders |
| Type | Effectiveness |
| Data Required | (N1) The answer to survey question Q4; A number between 1 and 5 from surveyed entities (or N/A) |
| Calculation | N1 |
| Measure | Number |
| Notes | This metric is designed to be bundled with other survey results from 6.5a. |
Metrics: The following metrics are defined for this function:
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Number of crisis communications distributed to constituents |
| Description | Tracks the total number of crisis-related communications sent to constituents during the course of a specific crisis. This provides a quantitative measure of outreach effort and messaging activity. |
| Type | Implementation |
| Data Required | (N1) Total number of crisis-related communications sent to constituents |
| Calculation | N1 |
| Measure | Number |
| Notes | Requires clear tagging or classification of messages as “crisis-related” in the communication platform or log. This metric should be tracked over a period such as days or weeks, as crises can vary greatly in length. If there is a defined target for frequency of crisis communications the metric can be used to indicate level of compliance. Can be broken down further by communication type (email, SMS, portal update) or by constituent group |
| Metric Attribute | Details |
|---|---|
| Name | Time from crisis onset to first communication to constituents |
| Description | Measures the responsiveness of the CSIRT communication process during a crisis by tracking how quickly the first message is sent following formal recognition of the crisis. |
| Type | Efficiency |
| Data Required | (N1) Timestamp of crisis onset (N2) Timestamp of first communication to any constituent |
| Calculation | N2 - N1 |
| Measure | Number |
| Notes | Depends on clear documentation of crisis declaration time and communication logs. Particularly valuable for assessing preparedness and the agility of internal processes. |
| Metric Attribute | Details |
|---|---|
| Name | Percentage of constituent groups reached during crisis communication |
| Description | Assesses the breadth of communication coverage during a crisis by calculating the percentage of defined constituent groups that received at least one message. |
| Type | Effectiveness |
| Data Required | (N1) Number of constituent groups that received at least one crisis communication (N2) Total number of defined constituent groups |
| Calculation | (N1 / N2) × 100 |
| Measure | Ratio |
| Notes | Requires a well-maintained list of constituent groups and accurate delivery tracking per group. Can be further analysed by priority level or geography |
| Metric Attribute | Details |
|---|---|
| Name | Percentage of communications acknowledged or acted upon by constituents |
| Description | Measures the proportion of crisis messages that received a meaningful acknowledgment or prompted a recorded action by the recipient, helping gauge message effectiveness and trust. |
| Type | Impact |
| Data Required | (N1) Number of crisis communications acknowledged or acted upon by constituents (N2) Total number of crisis communications distributed |
| Calculation | (N1 / N2) × 100 |
| Measure | Percentage |
| Notes | Requires response tracking, either via read receipts, follow-up action logs, or ticket responses. Can be a proxy indicator for both trust in the CSIRT and the relevance/clarity of the message. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Time to deliver initial status report after crisis declaration |
| Description | Measures the responsiveness of the CSIRT in providing its first situational update after a crisis has been formally declared. |
| Type | Efficiency |
| Data Required | (N1) Time of crisis declaration (N2) Time of first status report delivery |
| Calculation | (N2) - (N1) |
| Measure | Number |
| Notes | Depends on accurate timestamping of both the crisis declaration and report delivery. Can be benchmarked against policy-defined expectations for initial reporting. Statistical analysis can be performed across a set of times, such as mean or median. |
| Metric Attribute | Details |
|---|---|
| Name | Percentage of status reports delivered on time |
| Description | Evaluates how consistently the CSIRT meets pre-established deadlines for delivering crisis-related status reports. |
| Type | Effectiveness |
| Data Required | (N1) Number of status reports delivered on time (N2) Total number of status reports expected during the crisis |
| Calculation | (N1) / (N2) * 100 |
| Measure | Percentage |
| Notes | Requires a pre-defined reporting schedule and consistent tracking of both expectations and actual delivery times. May be influenced by both internal delays and external coordination issues |
The following metric is defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Time from operational impact to external notification |
| Description | Measures the elapsed time between the time at which normal CSIRT operations are negatively impacted and when that information is communicated externally. |
| Type | Efficiency |
| Data Required | (N1) Time at which operational decision was made (N2) Time of corresponding external notification |
| Calculation | Mean(N2 − N1) |
| Measure | Mean |
| Notes | Capturing decision timestamps accurately may be difficult during fast-moving crises. Useful for evaluating the responsiveness of CSIRT communications. |
Each functional area within the six services has associated metrics. In addition, here are four program-wide metrics for the Vulnerability Management service area, designed to provide insight into the overall performance, risk posture, and operational maturity of the vulnerability management service area. Each metric cuts across multiple services and functions in Section 7 and is presented in the standard metrics format.
The following program metrics are included in this Service Area:
| Metric Attribute | Details |
|---|---|
| Name | Total number of vulnerabilities handled per reporting period |
| Description | Measures the volume of vulnerabilities processed by the organisation across all intake, analysis, coordination, and response activities. |
| Type | Implementation |
| Data Required | (N1) Count of all unique vulnerabilities recorded and processed |
| Calculation | N1 |
| Measure | Number |
| Notes | Requires centralized vulnerability tracking. May need deduplication of records from different services. Serves as a high-level indicator of workload or threat landscape exposure. |
| Metric Attribute | Details |
|---|---|
| Name | Percentage of vulnerabilities with defined remediation or mitigation |
| Description | Indicates how many of the vulnerabilities processed resulted in an actionable plan to remediate or mitigate. |
| Type | Effectiveness |
| Data Required | (N1) Number of vulnerabilities handled (N2) Number of vulnerabilities for which remediation or mitigation was defined |
| Calculation | (N2 / N1) × 100 |
| Measure | Percentage |
| Notes | May require validation across multiple teams (e.g., analysis, coordination, IT). Highlights maturity in turning discovery into action. |
| Metric Attribute | Details |
|---|---|
| Name | Average time from vulnerability intake to remediation |
| Description | Captures end-to-end efficiency from receiving a report to executing a solution. |
| Type | Efficiency |
| Data Required | (N1) Time of vulnerability intake (report receipt or discovery) (N2) Time of remediation (patch or mitigation applied) |
| Calculation | N2 − N1 (averaged across all vulnerabilities) |
| Measure | Mean |
| Notes | Requires time correlation across functions and possibly across teams. Useful in identifying where delays occur across the full lifecycle. |
| Metric Attribute | Details |
|---|---|
| Name | Distribution of vulnerabilities by severity and asset class |
| Description | Categorizes vulnerabilities to assess risk concentration and trends. |
| Type | Impact |
| Data Required | Severity level (e.g., CVSS or High/Medium/Low, etc.) Asset class (e.g., data center, endpoint, IoT) |
| Calculation | No calculation. Show trending counts or aggregate statistics across severities and classes. |
| Measure | Number |
| Notes | Requires accurate classification and asset inventory mapping. Can inform targeted investments or patch prioritization policies. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Number of vulnerabilities identified during incident handling |
| Description | Tracks the total number of vulnerabilities discovered through investigation of security incidents. Includes both known and previously unknown (zero-day) vulnerabilities. |
| Type | Implementation |
| Data Required | (N1) Number of vulnerabilities identified as part of incident handling |
| Calculation | N1 |
| Measure | Number |
| Notes | Requires integration between incident handling records and vulnerability tracking systems; consistent documentation practices are essential. Useful for understanding how much vulnerability discovery occurs organically through reactive investigation. |
| Metric Attribute | Details |
|---|---|
| Name | Time from incident detection to vulnerability identification |
| Description | Measures the elapsed time between the detection of an incident and the identification of an exploited vulnerability. |
| Type | Efficiency |
| Data Required | (N1) Timestamp of incident detection (N2) Timestamp when the vulnerability was identified |
| Calculation | N2 - N1 |
| Measure | Number |
| Notes | Requires precise and consistent timestamping of both detection and analysis milestones. Indicates how quickly the CSIRT can recognize the root cause of an incident at the vulnerability level. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Number of vulnerabilities identified from public or third-party sources |
| Description | Tracks the total number of new vulnerabilities discovered by CSIRT staff through public sources or restricted third-party services. |
| Type | Implementation |
| Data Required | (N1) Number of vulnerabilities identified from public or third-party sources |
| Calculation | N1 |
| Measure | Number |
| Notes | Requires systematic tracking of source-monitoring activities; some findings may be duplicated across sources or already known. Can be broken down by source type (e.g., mailing list, vendor site, paid service) and specific source for trend analysis. |
| Metric Attribute | Details |
|---|---|
| Name | Time from public disclosure to identification by CSIRT |
| Description | Measures the delay between the public or third-party disclosure of a vulnerability and the point at which CSIRT staff formally identify or log it. |
| Type | Impact |
| Data Required | (N1) Timestamp of public or third-party disclosure (N2) Timestamp of CSIRT identification |
| Calculation | N2 - N1 |
| Measure | Number |
| Notes | May require integration with source monitoring tools or manual tracking; disclosure time may be unclear or approximate. Shorter times indicate more responsive monitoring and better situational awareness. |
Metrics: The following metric is defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Number of new vulnerabilities identified by CSIRT |
| Description | This is a simple count of how many new vulnerabilities were discovered by the CSIRT per period (year/month). It tracks the number of new vulnerabilities discovered by the CSIRT through deliberate research activities, such as fuzz testing or reverse engineering. |
| Type | Implementation |
| Data Required | (N1) Number of new vulnerabilities discovered by the CSIRT |
| Calculation | N1 |
| Measure | Number |
| Notes | Requires consistent internal documentation and confirmation that the vulnerability is indeed new (not already catalogued by others). Can be further categorized by discovery methods (e.g., fuzzing, reverse engineering, static analysis) for internal reporting. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Number of vulnerability reports received from external sources |
| Description | Tracks the total number of vulnerability reports received from constituents or third parties during a defined period. |
| Type | Implementation |
| Data Required | (N1) Number of vulnerability reports received through official channels |
| Calculation | N1 |
| Measure | Number |
| Notes | Requires consistent tagging or classification of reports as "vulnerability reports" and central logging of all intake channels. Can be broken down by source type (e.g., constituent, researcher, PSIRT) or intake method (email, portal). |
| Metric Attribute | Details |
|---|---|
| Name | Vulnerability reporting channel up time |
| Description | Measures the percentage of time that the CSIRT's advertised vulnerability reporting channels (e.g., email, web form, portal) are available and functioning. |
| Type | Implementation |
| Data Required | (N1) Total operational time of reporting channels (N2) Total time in the monitoring period |
| Calculation | N1 / N2 * 100 |
| Measure | Number |
| Notes | Requires automated monitoring tools or manual tracking of uptime across intake mechanisms. Downtime may result in lost or delayed reports; this is critical for maintaining trust and accessibility. |
| Metric Attribute | Details |
|---|---|
| Name | Time to acknowledge vulnerability report |
| Description | This metric measures the amount of time it takes your team to acknowledge receipt of the vulnerability report. |
| Type | Efficiency |
| Data Required | (N1) Time at which the vulnerability report was received (N2) Time at which the vulnerability report was acknowledged |
| Calculation | N2 - N1 |
| Measure | Number |
| Notes | Requires clear logging of both report receipt time and acknowledgment time. Helps evaluate professionalism and responsiveness in early-stage communication with reporters. As with other "time to" metrics, this can be analysed statistically, e.g., median time to acknowledge. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Percentage of vulnerability reports triaged within defined time frame |
| Description | Measures how many received reports were reviewed, categorized, and acted upon (e.g., forwarded or dismissed) within a policy-defined period (e.g., 3 business days). |
| Type | Efficiency |
| Data Required | (N1) Number of reports triaged within defined time frame (N2) Total number of reports received |
| Calculation | (N1 / N2) × 100 |
| Measure | Percentage |
| Notes | Requires accurate tracking of intake, triage timestamps, and clear definition of what constitutes triage completion. Reflects responsiveness and operational discipline in early vulnerability handling. |
| Metric Attribute | Details |
|---|---|
| Name | Percentage of vulnerability reports forwarded for handling |
| Description | Measures the proportion of received reports that were formally routed for follow-up (e.g., passed to a Vulnerability Analysis service or external party) after triage. |
| Type | Implementation |
| Data Required | (N1) Number of reports forwarded after triage (N2) Total number of triaged reports |
| Calculation | (N1 / N2) × 100 |
| Measure | Percentage |
| Notes | Requires clear recordkeeping and defined criteria for routing decisions. Indicates how often reports are considered actionable enough for further attention, either internally or externally. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Vulnerabilities categorized and prioritized within defined time frame |
| Description | Measures how many confirmed vulnerabilities were categorized and prioritized within a predefined time window (e.g., 3 business days) following assignment to the analysis team. |
| Type | Efficiency |
| Data Required | (N1) Number of vulnerabilities categorized and prioritized within timeframe (N2) Total number of confirmed vulnerabilities received for triage |
| Calculation | (N1 / N2) * 100 |
| Measure | Percentage |
| Notes | Requires clear tracking of handoff and triage completion timestamps; categories and prioritization levels must be formally recorded. Reflects timeliness in preparing vulnerabilities for further analysis or coordination. |
| Metric Attribute | Details | |
|---|---|---|
| Name | Distribution of vulnerabilities by category | |
| Description | Tracks the proportion of vulnerabilities assigned to each predefined category during triage, helping to identify trends in vulnerability types over time. | |
| Type | Impact | |
| Data Required | (N1) Number of vulnerabilities per category (e.g., N1a = injection, N1b = misconfiguration, etc.) (N2) Total number of vulnerabilities categorized |
|
| Calculation | for each category x: (N1x / N2) × 100 |
|
| Measure | Percentage | |
| Notes | Requires a standardized and enforced categorization scheme; may be hard to compare across analysts or time periods without normalization. Useful for trend analysis, capacity planning, and directing training or tooling improvements. |
|
Metrics: The following metric is defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Percentage of vulnerabilities with documented root cause and exploitation conditions |
| Description | Measures how many vulnerabilities have a completed analysis that includes both the underlying root cause (e.g., design or implementation flaw) and the conditions under which the vulnerability could be exploited. |
| Type | Implementation |
| Data Required | (N1) Number of vulnerabilities with documented root cause and exploitation conditions (N2) Total number of vulnerabilities accepted for analysis |
| Calculation | (N1 / N2) * 100 |
| Measure | Percentage |
| Notes | Requires clear documentation standards; some analyses may remain incomplete due to limited access to source code, limited context, or dependency on third-party vendors. This metric reflects completion of a full root cause analysis as defined by the function outcome. In cases where only the root cause or exploitation conditions are identified, but not both, the vulnerability is not counted in (N1). Partial findings may still be valuable and can be tracked separately through internal flags or workflow statuses. |
Metrics: The following metric is defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Percentage of analysed vulnerabilities with documented remediation or mitigation plan |
| Description | Measures how many vulnerabilities, once analysed, resulted in a documented remediation (e.g., patch, code change) or mitigation (e.g., workaround, configuration guidance) plan. |
| Type | Implementation |
| Data Required | (N1) Number of vulnerabilities with documented remediation or mitigation plans (N2) Total number of vulnerabilities analysed |
| Calculation | (N1 / N2) * 100 |
| Measure | Percentage |
| Notes | CSIRTs may rely on vendors or third parties for fixes, which can delay or limit visibility; mitigation strategies may be incomplete or unofficial. This metric reflects whether an actionable plan was established, regardless of who develops or applies it. Vulnerabilities documented as accepted risks (with justification) may be excluded from (N1) or tracked separately depending on organisational policy. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Vulnerabilities for which notification was sent to appropriate parties |
| Description | Measures how many confirmed vulnerabilities were reported to at least one relevant CVD participant (e.g., vendor, PSIRT, coordinator) as part of the disclosure and coordination process. |
| Type | Implementation |
| Data Required | (N1) Number of vulnerabilities for which notification was sent to a relevant CVD participant (N2) Total number of confirmed vulnerabilities requiring notification |
| Calculation | (N1 / N2) * 100 |
| Measure | Percentage |
| Notes | Requires clear documentation of notification attempts and recipient relevance; some parties may be hard to identify or reach. "Appropriate parties" should be defined in your coordination policy or process. This metric reflects completeness of outreach, not the quality of response. |
| Metric Attribute | Details |
|---|---|
| Name | Vulnerability - time to notify |
| Description | Captures the raw time interval between the confirmation of a vulnerability and the moment external parties are notified. This provides a baseline for statistical analysis and operational review. |
| Type | Efficiency |
| Data Required | (N1) Time of vulnerability confirmation (N2) Time of vulnerability notification |
| Calculation | N2 - N1 |
| Measure | Number |
| Notes | Requires accurate and auditable logging of confirmation and notification events. Use statistical analysis tools (e.g., median, percentiles) separately to identify trends, outliers, or policy deviations. |
Metrics: No metrics are defined for this function. While the function is essential to coordinated vulnerability disclosure it is not independently measurable due to its reliance on external stakeholder actions and informal communication dynamics.
Metrics: No metrics are defined for this function. It establishes foundational policy and infrastructure but does not yield directly measurable outcomes appropriate for routine performance metrics. If measuring if policy updates or stakeholder transparency become part of an audit or maturity initiative, consider adding metrics such as percentage of constituents with access to policy or number/frequency of updates to policy.
Metrics: The following metric is defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Time to disseminate vulnerability information |
| Description | Measures the elapsed time between receipt of a vulnerability report and dissemination of constituent- or public-facing vulnerability information. Indicates how quickly the CSIRT can deliver actionable insights. |
| Type | Efficiency |
| Data Required | (N1) Time of vulnerability report receipt (N2) Time of vulnerability information dissemination |
| Calculation | N2 - N1 |
| Measure | Number |
| Notes | Timing may be affected by dependency on vendor coordination, internal review cycles, or communication policy constraints. Use of the median is preferred to mitigate the effect of outliers. Be clear on what constitutes "dissemination" (e.g., advisory publication, direct communication, etc.). |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Percentage of post-disclosure inquiries responded to within defined time frame |
| Description | Tracks the percentage of constituent or stakeholder inquiries received after a vulnerability disclosure that are responded to within a pre-established timeframe. This reflects the responsiveness and readiness of the CSIRT to support constituents. |
| Type | Effectiveness |
| Data Required | (N1) Total number of post-disclosure inquiries received (N2) Number of inquiries responded to within the defined time frame |
| Calculation | (N2 / N1) * 100 |
| Measure | Percentage |
| Notes | May require integration between feedback channels and case management systems to track timing accurately. The defined time frame should be consistent with expectations (e.g., 48 or 72 hours). Median response time may also be tracked for internal review. |
| Metric Attribute | Details |
|---|---|
| Name | Number of follow-up incidents or implementation issues reported by constituents |
| Description | Measures how many constituents report either new incidents or implementation challenges related to the disclosed vulnerability. This provides insight into disclosure clarity and the downstream impact of vulnerability communication. |
| Type | Impact |
| Data Required | (N1) Number of follow-up incident reports or implementation challenges referencing a disclosed vulnerability |
| Calculation | N1 |
| Measure | Number |
| Notes | Requires tagging or associating post-disclosure reports with specific disclosures. May inform future improvements in communication format, mitigation guidance, or constituent outreach. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Vulnerability scanning coverage |
| Description | Measures the percentage of in-scope assets that are covered by vulnerability scanning activities. |
| Type | Effectiveness |
| Data Required | (N1) Number of in-scope assets (N2) Number of in-scope assets scanned for vulnerabilities |
| Calculation | (N2 / N1) * 100 |
| Measure | Percentage |
| Notes | Requires complete and accurate asset inventory, and integration with scanning tools. Helps assess the breadth of detection efforts. Partial scans or intermittent asset availability can impact this metric. Depending on the types of vulnerability scans defined by your organisation and the criticality of your scanned assets, you will want to break down your numbers by these variables. |
| Metric Attribute | Details |
|---|---|
| Name | Number of penetration tests conducted |
| Description | Tracks the number of formal penetration tests performed within a given period. |
| Type | Implementation |
| Data Required | (N1) Count of completed penetration tests |
| Calculation | N1 |
| Measure | Number |
| Notes | Requires a consistent definition of what constitutes a penetration test and centralized tracking. Useful for tracking program maturity and compliance with policies or regulations that require periodic testing. |
| Metric Attribute | Details |
|---|---|
| Name | Average time from vulnerability disclosure to first scan |
| Description | Measures the responsiveness of the organisation in initiating detection efforts following a known vulnerability announcement. |
| Type | Efficiency |
| Data Required | (N1) Time of public disclosure of the vulnerability (N2) Time of first scan or assessment for that vulnerability |
| Calculation | N2 −–N1 Averaged across relevant time spans |
| Measure | Mean |
| Notes | Requires timestamped records of both vulnerability disclosure events and scan activities. Coordination may be required. Helps assess how quickly detection processes are triggered after new threats emerge. Outlier events may warrant additional review. |
Metrics: The following metrics are defined for this function:
| Metric Attribute | Details |
|---|---|
| Name | Mean time to remediate detected vulnerabilities |
| Description | Measures the average elapsed time between the detection of a vulnerability and its remediation, reflecting how quickly known risks are addressed. |
| Type | Efficiency |
| Data Required | (N1) Time of vulnerability detection (N2) Time of vulnerability remediation |
| Calculation | N2 −–N1 (averaged across all relevant vulnerabilities and time spans) |
| Measure | Mean |
| Notes | Requires integration of vulnerability detection and patch management records with accurate timestamps. Can help identify bottlenecks in the remediation pipeline. Outliers may require deeper investigation or policy exception tracking. |
| Metric Attribute | Details |
|---|---|
| Name | Percentage of high-severity vulnerabilities remediated within defined time frame |
| Description | Assesses the organisation's ability to meet remediation targets for vulnerabilities with high severity or risk ratings. |
| Type | Effectiveness |
| Data Required | (N1) Number of high-severity vulnerabilities detected (N2) Number of high-severity vulnerabilities remediated within defined timeframe |
| Calculation | (N2 / N1) * 100 |
| Measure | Percentage |
| Notes | Requires consistent severity classification (e.g., CVSS) and policy-driven remediation timeframes. A key compliance and risk metric often aligned with internal SLAs or regulatory requirements. |
Alert – A notification generated by a detection mechanism indicating a potential security event or security incident.
Artefact – A digital object or data item collected during incident response or analysis, such as a file, memory image, network capture, or log extract.
Capability – A measurable activity that may be performed as part of an organization's roles and responsibilities. For the purposes of the FIRST services framework, the capabilities can either be defined as the broader services or as the requisite functions.
Capacity – The number of simultaneous process-occurrences of a particular capability that an organization can execute before they achieve some form of resource exhaustion.
Chain of custody – The documented process that ensures the integrity and authenticity of data or artefacts from collection through analysis and potential legal use.
Constituent – An individual, group, or organization that is served by, or otherwise relies on, the CSIRT.
Containment – Actions taken to limit the spread or impact of a security incident.
Coverage – The extent to which controls, detection mechanisms, or services address identified threats, assets, or requirements.
Data required – The discrete data elements necessary to calculate or understand a metric, listed within each metric definition and reset per metric.
Dynamic (runtime) analysis – Analysis of an artefact by executing it in a controlled environment to observe its behaviour.
Efficiency metric – A metric that examines timeliness or resource utilization, including how quickly activities are performed and issues are addressed.
Effectiveness metric – A metric that evaluates how well a service, function, or control achieves its intended outcome.
False positive – An alert, detection, or reported condition that is determined not to represent malicious or relevant activity.
Function – An activity or set of activities aimed at fulfilling the purpose of a particular service.
Impact metric – A metric that articulates the effect of information security activities on organizational mission, goals, objectives, or value.
Implementation metric – A metric that demonstrates the presence, completeness, or progress of controls, processes, or capabilities.
Indicator of compromise (IOC) – A piece of information associated with an incident that can be used to identify potentially malicious activity, such as IP addresses, domains, file hashes, registry keys, or process names.
Measure – The form of the metric result, such as Percentage, Mean, Median, Number, or Ratio.
Metric – A quantitative or qualitative measurement used to assess the performance, effectiveness, efficiency, coverage, or impact of a CSIRT service or function.
Metric type – A classification describing the primary intent of a metric, used to indicate what aspect of a service or function is being measured.
Recovery – Actions taken to restore systems and services to normal operation following a security incident.
Root cause – The underlying reason why a security incident occurred, beyond immediate symptoms or indicators.
Security event – An observable occurrence in a system or network that may indicate a security-relevant condition.
Security incident – A security event or series of events that has been determined to have a negative impact on confidentiality, integrity, or availability.
Service – A set of recognizable, coherent functions oriented toward a specific result that may be expected or required by constituents or stakeholders.
Service area – A grouping of services related to a common aspect, used to organize services at a top level to facilitate understanding and communication.
Situational awareness – An understanding of the current state of incidents, threats, and response activities sufficient to support effective decision-making.
Stakeholder – An individual or organization that has an interest in the CSIRT's services, performance, or outcomes, but may not directly receive services.
Static analysis – Analysis of an artefact without executing it, such as examining file structure, metadata, or code.
Triage – The process of reviewing, categorizing, and prioritizing events, alerts, or incidents to determine appropriate handling.
True positive – An alert, detection, or reported condition that correctly identifies malicious or relevant activity.
Vulnerability – A weakness in a system, service, or configuration that could be exploited to compromise security.
Vulnerability disclosure – The process of communicating information about vulnerabilities to affected parties, vendors, or the public.
Asana.org
Story points: Estimation guide for user stories in Agile
https://asana.com/resources/story-points
FIRST.org
CSIRT Services Framework v2.1. Forum of Incident Response and Security Teams (FIRST), 2023.
https://www.first.org/standards/frameworks/csirt-services
FIRST.org
Service Incident Timing Metrics v1. Forum of Incident Response and Security Teams (FIRST), 2023.
https://www.first.org/global/sigs/metrics/Security-Incident-Timing-Metrics_v1.0.pdf
ISO/IEC 30111:2019
Information technology – Security techniques – Vulnerability handling processes, International organisation for Standardization
ISO/IEC 29147:2018
Information technology – Security techniques – Vulnerability disclosure. International organisation for Standardization
NIST SP 800-61 Rev. 2
Computer Security Incident Handling Guide. National Institute of Standards and Technology (NIST), 2012
NIST SP 800-55v1
Measurement Guide for Information Security - Volume 1, Identifying and Selecting Measures, National Institute of Standards and Technology (NIST), 2024
NIST SP 800-115
Technical Guide to Information Security Testing and Assessment. NIST, 2008
NIST NVD (National Vulnerability Database)
https://nvd.nist.gov/
Common Vulnerability Scoring System (CVSS) v3.1
FIRST.org
https://www.first.org/cvss/
CERT/CC
Vulnerability Disclosure Policy. Carnegie Mellon University Software Engineering Institute
https://www.kb.cert.org/vuls/html/disclosure
ENISA
Coordinated Vulnerability Disclosure Guidelines. European Union Agency for Cybersecurity, 2018
https://www.enisa.europa.eu/publications/coordinated-vulnerability-disclosure-guidelines

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