Improper access control in Apache Tomcat - CVE-2026-66422
Published: August 26, 2026
Vulnerability identifier: #VU145384
CSH Severity: Low
CVSS v4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-66422
CWE-ID: CWE-284
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to bypass declarative role constraints.
The vulnerability exists due to improper access control in Realm role handling when processing security-role-ref definitions. A remote user can use servlet role references as role aliases to bypass declarative role constraints.
Affected software
Apache Tomcat
How to mitigate CVE-2026-66422
Install security update from vendor's website.
Apache Tomcat - addressed in versions 9.0.121, 10.1.59, 11.0.25