Improper access control in Apache Tomcat - CVE-2026-66422

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

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.

Apache Tomcat
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server 15 SP4
SUSE Linux Enterprise Server 15 SP5
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise High Performance Computing ESPOS 15
SUSE Linux Enterprise High Performance Computing LTSS 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise High Performance Computing 12
Web and Scripting Module
ApplinX
tomcat-jsp-2_3-api
tomcat-el-3_0-api
tomcat-javadoc
tomcat-webapps
tomcat-docs-webapp
tomcat-admin-webapps
tomcat
tomcat-lib
tomcat-servlet-4_0-api

Install security update from vendor's website.

Apache Tomcat - addressed in versions 9.0.121, 10.1.59, 11.0.25
tomcat-jsp-2_3-api - addressed in versions 9.0.121-3.177.3, 9.0.121-150200.120.1
tomcat-el-3_0-api - addressed in versions 9.0.121-3.177.3, 9.0.121-150200.120.1
tomcat-javadoc - update to 9.0.121-3.177.3
tomcat-webapps - addressed in versions 9.0.121-3.177.3, 9.0.121-150200.120.1
tomcat-docs-webapp - update to 9.0.121-3.177.3
tomcat-admin-webapps - addressed in versions 9.0.121-3.177.3, 9.0.121-150200.120.1
tomcat - addressed in versions 9.0.121-3.177.3, 9.0.121-150200.120.1
tomcat-lib - addressed in versions 9.0.121-3.177.3, 9.0.121-150200.120.1
tomcat-servlet-4_0-api - addressed in versions 9.0.121-3.177.3, 9.0.121-150200.120.1

• https://lists.apache.org/api/email.lua?id=dywhxs7v9c9ww1xvv7h4102vn50hx3sh
• https://tomcat.apache.org/security-11.html

• Multiple vulnerabilities in Apache Tomcat
• SUSE update for tomcat
• SUSE update for tomcat
• Multiple vulnerabilities in IBM ApplinX