What is CVE-2026-53434?

CVE-2026-53434 is a critical-severity vulnerability in Apache Tomcat, classified under CWE-390. CVSS score: 9.1/10. Published 2026-06-29.

How severe is CVE-2026-53434?

Critical severity. CVSS v3 base score is 9.1 out of 10.

Vulnerability in Apache Tomcat

CVE-2026-53434

Detection of Error Condition Without Action vulnerability in Apache Tomcat when configuring CRLs for a FFM based connector. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M7 through 10.1.55, from 9.0.83 through 9.0.118. Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119, which fixes the issue.

Published 2026-06-29 · last modified 2026-07-02.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.006 (46.4th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 46.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.006 · change: +0.001

Affected products

Apache Tomcat
Apache Software Foundation Tomcat — versions 11.0.0-M1, 10.1.0-M7, 9.0.83

Weakness classification (CWE)

CWE-390

References

lists.apache.org/thread/x510lbq0sfrd1qyo7q3r1mpllgpdcosk (vendor-advisory, Mailing List, Vendor Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Third Party Advisory)

Frequently asked questions

What is CVE-2026-53434?: CVE-2026-53434 is a critical-severity vulnerability in Apache Tomcat, classified under CWE-390. CVSS score: 9.1/10. Published 2026-06-29.
How severe is CVE-2026-53434?: Critical severity. CVSS v3 base score is 9.1 out of 10.