Understanding Exploit Maturity

This knowledge base article will give insight into:

Definition of exploit maturity
Differences between exploit maturity and proof of concept exploit
Relationship between exploit maturity and vulnerability severity
Relationship between exploit maturity and vulnerability criticality
Impact of exploit maturity on the risk a vulnerability poses
How vulnerability management teams can use explicit maturity when prioritizing remediation actions

Exploit maturity is a metric that reflects the current state of exploit techniques for a specific vulnerability, the availability of exploit code, and active exploitation in the wild. Originally introduced as a temporal metric in the Common Vulnerability Scoring System (CVSS) v3.0, exploit maturity is now considered a threat metric in CVSS v.4.0.

This metric considers an exploit’s lifecycle from initial vulnerability discovery through threat actors’ ability to weaponize the vulnerability to gain unauthorized access or damage an IT system.

For example, while a theoretical exploit indicates that malicious actors could conceivably use a vulnerability to help achieve their objectives, easy-to-use exploit code available on the dark web means that less sophisticated or technical cybercriminals can deploy attacks more easily.

The exploit maturity metric includes four categories:

Not defined: Default metric indicating a lack of reliable threat intelligence.
Proof of Concept: Threat intelligence indicates that theoretical exploit code is available but no reported attempts or publicly available solutions to simplify attempts exist.
Attacked: Threat intelligence indicates either known attempted or successful attacks already target the vulnerability, or tools to enable exploits are known to exist, such as exploit kits being sold on the dark web.
Unreported: Available threat intelligence indicates no publicly available proof-of-concept code, reported knowledge of exploit attempts, and no publicly available solutions that simplify attempts to exploit the vulnerability.

As the CVSS does not populate the exploit maturity values, organizations need sources of exploit intelligence that incorporate this information so they can implement the appropriate detections and remediation strategies.

What is the Difference Between Exploit Maturity and a Proof of Concept Exploit?

Proof of concept (PoC) is one stage of an exploit’s maturity. An exploit PoC is a preliminary demonstration showing how attackers could exploit the vulnerability, even if threat actors have not actually engaged in hostile activity in the wild.

The four primary differences between exploit maturity and exploit PoC are:

Definition: Exploit maturity ranges from no exploit to fully weaponized exploit while exploit PoC only demonstrates an initial possibility.
Objective: Exploit maturity enables organizations to prioritize their strategies based on attackers using a vulnerability while exploit PoC indicates a potential risk that may or may not come to fruition.
Stage in development: Exploit maturity is a broader spectrum of threats and risks while exploit PoC is only an initial state prior to actual use.
Impact: Exploit maturity helps assess risk and potential real-world impact while exploit PoC validates a hypothetical way that attackers could use the vulnerability in an attack.

How Does Exploit Maturity Impact a Vulnerability’s Severity?

When the CVSS moved exploit maturity from a temporal to a threat metric, it highlighted the value that these insights provide when assessing a vulnerability’s severity. The threat metrics adjust a vulnerability’s severity by considering attackers’ ability to and ease of using the vulnerability over time to successfully achieve their objectives.

Organizations that consider exploit maturity’s relationship to vulnerability severity typically address the following:

Risk Perception: Higher exploit maturity can correlate to greater exploitability which increases the perceived threat levels.
Actual Risk Impact: Mature exploit code available publicly or privately allows less sophisticated and technical attackers to exploit the vulnerability, expanding the potential for harm to systems.
Severity Rating: Vulnerabilities with mature exploit code receive higher severity ratings since real-world exploitation is more likely.
Threat Intelligence: Weaponized and actively used exploits should be part of the threat intelligence that the security team gathers.

How Does Exploit Maturity Impact a Vulnerability's Criticality?

The CVSS scoring system defines a critical vulnerability as one with a score between 9.0 and 10.0 based on its combined Base, Threat, and Environmental scores. The Threat score incorporates exploit maturity, ultimately increasing the overall CVSS score. For example, vulnerabilities that fall into the Attacked exploit maturity category likely have a higher overall CVSS score compared to similarly situated vulnerabilities that have an exploit maturity level defined as Unreported.

How Does Exploit Maturity Impact the Risk a Vulnerability Poses to an IT Environment?

Security and vulnerability management teams should consider exploit maturity as a factor when determining the risk a vulnerability poses to their environments. As exploit techniques become more refined and accessible, the risk associated with a vulnerability can increase significantly. Some key considerations include:

Exploit code availability: If attackers are actively exploiting the vulnerability in the wild, they are also likely targeting the technology’s customer base.
Operationalization of the exploit: If the exploit is available for private or public sale, then more malicious actors can compromise systems that incorporate the technology and the IT environment’s risk increases.
Current security controls: To exploit a vulnerability, attackers need to be able to reach it within the context of the organization’s current security and system architecture so compensating controls, like network segmentation, may decrease risk.

How Does Exploit Maturity Help Vulnerability Management Teams Prioritize Remediation Efforts?

Exploit maturity significantly enhances vulnerability management by enabling teams to prioritize their remediation actions more effectively.

Some key benefits of using exploit maturity when trying to prioritize vulnerability remediation include:

Efficient Resource Allocation: Filtering vulnerabilities by exploit maturity allows teams to dedicate efforts towards addressing those with active threats that pose increased data breach risks.
Rapid Identification: Quickly ascertaining vulnerabilities with known exploits enables organizations to address critical issues faster.
Informed Decision-Making: The inclusion of Exploit Code Maturity within the CVSS Threat Metrics guides prioritization efforts by offering an assessment of present exploitability which correlates to potential increased risk.

How Does Exploit Intelligence Incorporate Exploit Maturity?

As the number of vulnerabilities continues to grow, security and vulnerability remediation teams need information about the ones that malicious actors are most likely to use in an attack. Attackers exploit or are likely to exploit only about 2-3% of disclosed vulnerabilities. Exploit Intelligence incorporates a vulnerability’s technical information and exploit maturity then correlates it with additional context like:

Exploit type: Adversary objectives, like gaining initial access, stealing sensitive information, or disrupting business operations.
Exploit timelines: An exploit’s evolution from PoC to available publicly or privately to help predict a vulnerability’s future potential impact.
Threat intelligence: Information about known threats, like ransomware families, botnets, and named threat actors, for actionable insights that help prioritize next steps.

VulnCheck Exploit Intelligence: Breadth and Depth of Vulnerability and Exploit Maturity Information

With VulnCheck Exploit & Vulnerability intelligence, security and vulnerability remediation teams gain access to a breadth of data that incorporates the NIST National Vulnerability Database (NVD) and CISA Known Exploited Vulnerability (KEV) catalog coupled with exploit intelligence that provides insight into real-world attacker activity.

With our Exploit Intelligence, organizations can rapidly improve their vulnerability prioritization and remediation capabilities with data about public and commercial exploits, including reported exploited, weaponized exploits, threat actors attributed with the vulnerability, ransomware campaigns using the vulnerability, and botnets attributed to the vulnerability.