Apache Tomcat: Bypass of rules in Rewrite Valve
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 through 11.0.5, from 10.1.0 through 10.1.39, from 9.0.0 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 [FIXED_VERSION], which fixes the issue.
02 / AFFECTED SOFTWARE
Affected packages
161 explicit affected versions
161 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
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 through 11.0.5, from 10.1.0 through 10.1.39, from 9.0.0 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 [FIXED_VERSION], which fixes the issue.
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.
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 [FIXED_VERSION], which fixes the issue.
05 / REFERENCES
Further evidence
- http://www.openwall.com/lists/oss-security/2025/04/28/3
- https://lists.apache.org/[email protected]
- https://lists.debian.org/debian-lts-announce/2025/07/msg00009.html
- https://nvd.nist.gov/vuln/detail/CVE-2025-31651
- https://github.com/apache/tomcat
- https://github.com/apache/tomcat/commit/066bf6b6a15a4e7e0941d4acf096841165b97098
- https://github.com/apache/tomcat/commit/175dc75fc428930034a6c93fb52f830d955d8e64
- https://github.com/apache/tomcat/commit/ee3ab548e92345eca0cbd1f01649eb36c6f29454
- https://github.com/apache/tomcat/commit/fbecc915a10c5a3d634c5e2c6ced4ff479ce9953
- https://tomcat.apache.org/security-10.html
- https://tomcat.apache.org/security-11.html
- https://tomcat.apache.org/security-9.html
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/31xxx/CVE-2025-31651.json