How severe is GHSA-4qrj-99r6-jfrh?

GHSA-4qrj-99r6-jfrh has a CVSS score of 4.8/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-4qrj-99r6-jfrh?

GHSA-4qrj-99r6-jfrh affects the following packages: org.jenkins-ci.plugins:email-ext (Maven). Ecosystems affected: Maven.

How do I fix GHSA-4qrj-99r6-jfrh?

Update org.jenkins-ci.plugins:email-ext to 2.76 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4qrj-99r6-jfrh is resolved across your whole dependency graph.

How do I detect GHSA-4qrj-99r6-jfrh in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.jenkins-ci.plugins:email-ext. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-4qrj-99r6-jfrh if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against GHSA-4qrj-99r6-jfrh?

O3 pinpoints whether GHSA-4qrj-99r6-jfrh is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-4qrj-99r6-jfrh actively exploited in the wild?

No public exploit code has been indexed for GHSA-4qrj-99r6-jfrh yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-4qrj-99r6-jfrh?

GHSA-4qrj-99r6-jfrh has an EPSS (Exploit Prediction Scoring System) score of 0.7%, placing it in the 48th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-4qrj-99r6-jfrh?

GHSA-4qrj-99r6-jfrh is classified as CWE-295 (CWE-295). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-4qrj-99r6-jfrh published, and has it been updated?

GHSA-4qrj-99r6-jfrh was published on May 24, 2022 and was last updated on February 16, 2024. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

GHSA-4qrj-99r6-jfrh: Missing hostname validation in Email Exten…

EPSS Exploitation Probability

via FIRST.org ↗

0.7%probability of exploitation in next 30 days

Lower Risk48th percentile+0.66%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

1 pkg affected

☕org.jenkins-ci.plugins:email-ext

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

Email Extension Plugin 2.75 and earlier does not perform hostname validation when connecting to the configured SMTP server. This lack of validation could be abused using a man-in-the-middle attack to intercept these connections.

Email Extension Plugin 2.76 validates the SMTP hostname when connecting via TLS by default. In Email Extension Plugin 2.75 and earlier, administrators can set the Java system property mail.smtp.ssl.checkserveridentity to true on startup to enable this protection. Alternatively, this protection can be enabled (or disabled in the new version) via the 'Advanced Email Properties' field in the plugin’s configuration in Configure System.

In case of problems, this protection can be disabled again by setting mail.smtp.ssl.checkserveridentity to false using either method.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.jenkins-ci.plugins:email-ext`	all versions	2.76

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.jenkins-ci.plugins:email-ext. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update org.jenkins-ci.plugins:email-ext to 2.76 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4qrj-99r6-jfrh is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-4qrj-99r6-jfrh is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-4qrj-99r6-jfrh. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Email Extension Plugin 2.75 and earlier does not perform hostname validation when connecting to the configured SMTP server. This lack of validation could be abused using a man-in-the-middle attack to intercept these connections. Email Extension Plugin 2.76 validates the SMTP hostname when connecting via TLS by default. In Email Extension Plugin 2.75 and earlier, administrators can set the Java system property `mail.smtp.ssl.checkserveridentity` to `true` on startup to enable this protection. Alternatively, this protection can be enabled (or disabled in the new version) via the 'Advanced Email

O3 Security · Impact-Aware SCA

Is GHSA-4qrj-99r6-jfrh in your dependencies?

O3 detects GHSA-4qrj-99r6-jfrh across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works

GHSA-4qrj-99r6-jfrh