Vulnerability in Apache Tomcat
CVE-2026-43513
Improper Handling of Case Sensitivity vulnerability in LockOutRealm in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.21, from 10.1.0-M1 through 10.1.54, from 9.0.0.M1 through 9.0.117, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Older unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.22, 10.1.55 or 9.0.118 which fix the issue.
EPSS: 0.005 (38.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
Affected products
- Apache Tomcat
- Apache Software Foundation Tomcat — versions 11.0.0-M1, 10.1.0-M1, 9.0.0.M1
Weakness classification (CWE)
References
- security@apache.org (vendor-advisory, Mailing List, Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-43513?
- CVE-2026-43513 is a high-severity vulnerability in Apache Tomcat, classified under Improper Handling of Case Sensitivity. CVSS score: 7.5/10. Published 2026-05-12.
- How severe is CVE-2026-43513?
- High severity. CVSS v3 base score is 7.5 out of 10.