What is CVE-2026-59083?

CVE-2026-59083 is a critical-severity vulnerability in Apache Tomcat, classified under CWE-177. CVSS score: 9.1/10. Published 2026-07-14.

How severe is CVE-2026-59083?

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

Vulnerability in Apache Tomcat

CVE-2026-59083

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 t…

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.

Affected products

Apache Tomcat
Apache Software Foundation Tomcat — versions 11.0.0-M1, 10.1.0-M1, 9.0.0.M1

Weakness classification (CWE)

CWE-177

References

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

Frequently asked questions

What is CVE-2026-59083?: CVE-2026-59083 is a critical-severity vulnerability in Apache Tomcat, classified under CWE-177. CVSS score: 9.1/10. Published 2026-07-14.
How severe is CVE-2026-59083?: Critical severity. CVSS v3 base score is 9.1 out of 10.