CVE-2026-59083

Critical · CVSS 9.1

Apache Tomcat — Improper Handling of URL Encoding (Hex Encoding) - Security Constraint Bypass via Rewrite Valve

CVSS: 9.1; nvd
EPSS: 0.16%; 5th pct
KEV: No
Class: other; CWE-177

Description

Improper Handling of URL Encoding (Hex Encoding) vulnerability in Apache Tomcat's rewrite valve allowed security constraint bypass for some configurations. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.23, from 10.1.0-M1 through 10.1.56, from 9.0.0.M1 through 9.0.119, from 8.5.0 through 8.5.100. Other versions that have reached end of support may also be affected. Users are recommended to upgrade to version 11.0.24, 10.1.57 or 9.0.120, which fix the issue.

Search profile — drives PoC discovery

Symbols RewriteValverewrite valvehex encodingURL encodingsecurity constraint bypassCWE-177rewrite.configorg.apache.catalina.valves.rewrite.RewriteValve

Keywords CVE-2026-59083Apache Tomcatrewrite valveURL encoding bypasshex encoding bypasssecurity constraint bypassTomcat rewriteCWE-177percent encoding bypassTomcat 11.0.23Tomcat 10.1.56Tomcat 9.0.119Tomcat 8.5.100

Versions: 11.0.0-M1 through 11.0.23, 10.1.0-M1 through 10.1.56, 9.0.0.M1 through 9.0.119, 8.5.0 through 8.5.100

References

Status: enriched · ingested 2026-07-14T18:00:20.000Z · profiled 2026-07-15T06:30:20.000Z