How severe is GHSA-ff77-26x5-69cr?

No CVSS score has been assigned to GHSA-ff77-26x5-69cr yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-ff77-26x5-69cr?

GHSA-ff77-26x5-69cr affects the following packages: org.apache.tomcat:tomcat-catalina (Maven), org.apache.tomcat:tomcat-catalina (Maven), org.apache.tomcat:tomcat-catalina (Maven), org.apache.tomcat.embed:tomcat-embed-core (Maven), org.apache.tomcat.embed:tomcat-embed-core (Maven), org.apache.tomcat.embed:tomcat-embed-core (Maven), org.apache.tomcat:tomcat-catalina (Maven), org.apache.tomcat.embed:tomcat-embed-core (Maven). Ecosystems affected: Maven.

How do I fix GHSA-ff77-26x5-69cr?

Update org.apache.tomcat:tomcat-catalina to 9.0.104 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-ff77-26x5-69cr is resolved across your whole dependency graph.

How do I detect GHSA-ff77-26x5-69cr in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.tomcat:tomcat-catalina. 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-ff77-26x5-69cr 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-ff77-26x5-69cr?

O3 pinpoints whether GHSA-ff77-26x5-69cr 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-ff77-26x5-69cr actively exploited in the wild?

No public exploit code has been indexed for GHSA-ff77-26x5-69cr 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-ff77-26x5-69cr?

GHSA-ff77-26x5-69cr has an EPSS (Exploit Prediction Scoring System) score of 4.2%, placing it in the 90th 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-ff77-26x5-69cr?

GHSA-ff77-26x5-69cr is classified as CWE-116 (CWE-116). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-ff77-26x5-69cr published, and has it been updated?

GHSA-ff77-26x5-69cr was published on April 28, 2025 and was last updated on February 4, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

GHSA-ff77-26x5-69cr: Apache Tomcat Rewrite rule bypass

EPSS Exploitation Probability

via FIRST.org ↗

4.2%probability of exploitation in next 30 days

Lower Risk90th percentile+3.98%

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

8 pkgs affected

☕org.apache.tomcat:tomcat-catalina☕org.apache.tomcat:tomcat-catalina☕org.apache.tomcat:tomcat-catalina☕org.apache.tomcat.embed:tomcat-embed-core☕org.apache.tomcat.embed:tomcat-embed-core☕org.apache.tomcat.embed:tomcat-embed-core☕org.apache.tomcat:tomcat-catalina☕org.apache.tomcat.embed:tomcat-embed-core

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

Improper Neutralization of Escape, Meta, or Control Sequences vulnerability in Apache Tomcat. For a subset of unlikely rewrite rule configurations, it was possible for a specially crafted request to bypass some rewrite rules. If those rewrite rules effectively enforced security constraints, those constraints could be bypassed.

This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.5, from 10.1.0-M1 through 10.1.39, from 9.0.0.M1 through 9.0.102. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.0 though 8.5.100. Other, older, EOL versions may also be affected.

Users are recommended to upgrade to version 9.0.104, 10.1.40 or 11.0.6, which fix the issue.

Affected Packages

8 total 6 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.apache.tomcat:tomcat-catalina`	≥ 9.0.76&&< 9.0.104	9.0.104
☕Maven	`org.apache.tomcat:tomcat-catalina`	≥ 10.1.10&&< 10.1.40	10.1.40
☕Maven	`org.apache.tomcat:tomcat-catalina`	≥ 11.0.0-M2&&< 11.0.6	11.0.6
☕Maven	`org.apache.tomcat.embed:tomcat-embed-core`	≥ 9.0.76&&< 9.0.104	9.0.104
☕Maven	`org.apache.tomcat.embed:tomcat-embed-core`	≥ 10.1.10&&< 10.1.40	10.1.40
☕Maven	`org.apache.tomcat.embed:tomcat-embed-core`	≥ 11.0.0-M2&&< 11.0.6	11.0.6

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.tomcat:tomcat-catalina. 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.apache.tomcat:tomcat-catalina to 9.0.104 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-ff77-26x5-69cr 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-ff77-26x5-69cr 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-ff77-26x5-69cr. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Improper Neutralization of Escape, Meta, or Control Sequences vulnerability in Apache Tomcat. For a subset of unlikely rewrite rule configurations, it was possible for a specially crafted request to bypass some rewrite rules. If those rewrite rules effectively enforced security constraints, those constraints could be bypassed. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.5, from 10.1.0-M1 through 10.1.39, from 9.0.0.M1 through 9.0.102. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.0 though 8.5.100. Other, older, EOL versions

O3 Security · Impact-Aware SCA

Is GHSA-ff77-26x5-69cr in your dependencies?

O3 detects GHSA-ff77-26x5-69cr 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-ff77-26x5-69cr