What is CVE-2026-34500?

CVE-2026-34500 is a medium-severity vulnerability in Apache Tomcat, classified under Improper Authentication. CVSS score: 6.5/10. Published 2026-04-09.

How severe is CVE-2026-34500?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Auth bypass in Apache Tomcat

CVE-2026-34500

CLIENT_CERT authentication does not fail as expected for some scenarios when soft fail is disabled and FFM is used in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M14 through 11.0.20, from 10.1.22 through 10.1.53, from 9.0.92 through 9.0.116. Users are recommended to upgrade to version 11.0.21, 10.1.54 or 9.0.117, which fixes the issue.

Vulnerability class: Broken Authentication

EPSS: 0.005 (38.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N.

Affected products

Apache Tomcat — versions 11.0.0
Apache Software Foundation Tomcat — versions 11.0.0-M14, 10.1.22, 9.0.92

Weakness classification (CWE)

CWE-287 — Improper Authentication

References

security@apache.org (vendor-advisory, Vendor Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2026-34500?: CVE-2026-34500 is a medium-severity vulnerability in Apache Tomcat, classified under Improper Authentication. CVSS score: 6.5/10. Published 2026-04-09.
How severe is CVE-2026-34500?: Medium severity. CVSS v3 base score is 6.5 out of 10.