CVE-2026-55276: Apache Tomcat: Logged effective web.xml is incomplete

Severity: critical (CVSS 9.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-29 · updated 2026-10-25
Weakness: CWE-670

Description

Always-Incorrect Control Flow Implementation vulnerability in Apache Tomcat meant that special roles and empty authorisation constraints were not included when the effective web.xml was logged. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.0.M1 through 9.0.118, from 8.5.0 through 8.5.100. Other versions that have reached end of support may also be affected. Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119 which fixes the issue.

Affected products

Apache Tomcat: before 9.0.119; from 10.1.0 before 10.1.56; from 11.0.0 before 11.0.23 — fixed in 9.0.119, 10.1.56, 11.0.23

How to fix

Upgrade to a fixed version: Apache Tomcat 9.0.119, 10.1.56, 11.0.23. Check the vendor advisory for mitigations.

References

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