CVE-2026-59083: Apache Tomcat

Critical severity, CVSS 9.1. EPSS: 0.4% chance of exploitation in the next 30 days.

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.

Affected products

• Apache Tomcat: up to and including 8.0.0; from 8.5.0, up to and including 8.5.100; from 9.0.0, up to and including 9.0.119; from 10.1.0, up to and including 10.1.56; from 11.0.0, up to and including 11.0.23

Published 2026-07-14. Last modified 2026-07-14.