CVE-2026-66422 Apache Tomcat: Servlet role references can bypass declarative role constraints
Attackers can bypass declarative role constraints in Apache Tomcat by exploiting improper handling of security-role-ref definitions, gaining unauthorized access.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-66422?
CVE-2026-66422 is a high-severity missing authorization vulnerability in Apache Tomcat, published on 25 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-285
Which versions are affected by CVE-2026-66422?
1 open source package ship an affected version, including tomcat. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
tomcat Bitnami | From 7.0.97 | 9.0.121, 10.1.58, 11.0.25 |
Products include Apache Tomcat.
How do I fix CVE-2026-66422?
Upgrade tomcat to a fixed version for your release line: 9.0.121, 10.1.58 or 11.0.25.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-66422 being exploited?
There is no known exploitation of CVE-2026-66422 in the wild and no public exploit code.
Other vulnerabilities in Apache Tomcat
Sources
Also known as BIT-tomcat-2026-66422, DEBIAN-CVE-2026-66422, GHSA-w3xg-786f-g788, MINI-4qph-4xgc-cf9h, MINI-hv9x-wfmc-wwx4, MINI-w3h8-739q-j6mh and 1 more.