CVE-2026-66422: Apache Tomcat: Servlet role references can bypass declarative role constraints

Severity: high (CVSS 8.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-25 · updated 2026-08-27
Weakness: CWE-285

Description

Improper Authorization vulnerability in Apache Tomcat cause by security-role-ref definitions being incorrectly used as role aliases within the Realm in additional to the correct usage with Request.isUserInRole(). This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.24, from 10.1.0-M1 through 10.1.57, from 9.0.25 through 9.0.120. The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.46 through 8.5.100, from 7.0.97 through 7.0.109. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.25, 10.1.58 or 9.0.121, which fix the issue.

Affected products

Apache Tomcat: from 7.0.97 through 7.0.109; from 8.5.46 before 9.0.121; from 10.1.0 before 10.1.58; from 11.0.0 before 11.0.25 — fixed in 10.1.58, 11.0.25, 9.0.121

How to fix

Upgrade to a fixed version: Apache Tomcat 10.1.58, 11.0.25, 9.0.121. Check the vendor advisory for mitigations.

References

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