CVE-2026-86350: Apache Software Foundation Apache Tomcat

Critical severity, CVSS 9.1. EPSS: 0.3% chance of exploitation in the next 30 days.

Inconsistent interpretation of HTTP/2 requests ('HTTP Request/Response smuggling') vulnerability in Apache Tomcat caused by a regression in fix for CVE-2026-41293 can trigger request header mix-up. This issue affects Apache Tomcat: from 11.0.22 through 11.0.25, from 10.1.55 through 10.1.59, from 9.0.118 through 9.0.121. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.

Affected products

• Apache Software Foundation Apache Tomcat: from 11.0.22, up to and including 11.0.25; from 10.1.55, up to and including 10.1.59; from 9.0.118, up to and including 9.0.121

Published 2026-09-23. Last modified 2026-09-23.