Quick answers
- Is CVE-2026-66422 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-66422 being exploited in the wild.
- How severe is CVE-2026-66422?
- High severity, with a CVSS score of 8.1, published 25 August 2026.
- Which products and versions are affected?
- Apache Tomcat 11.0.0-M1 through 11.0.24, 10.1.0-M1 through 10.1.57, 9.0.25 through 9.0.120, 8.5.46 through 8.5.100, 7.0.97 through 7.0.109.
- Is there a fix for CVE-2026-66422?
- A patch was published on 2026-08-25: Fixes released in versions 11.0.25, 10.1.58, and 9.0.121 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-66422 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-66422?
- Check whether you run Apache Tomcat at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability is an improper authorization issue in Apache Tomcat's Realm component, where security-role-ref definitions are incorrectly used as role aliases in addition to their correct usage with Request.isUserInRole(). This causes role-based access control (RBAC) checks to be bypassed when declarative role constraints are in place. The attack requires network access to a Tomcat instance hosting a vulnerable application, but does not require authentication or user interaction to exploit. An attacker can craft requests that exploit the mishandled role aliases to gain unauthorized access to protected servlets or resources. Fixes are available in Apache Tomcat 11.0.25, 10.1.58, and 9.0.121.
Affected products
- Apache Tomcat 11.0.0-M1 through 11.0.24, 10.1.0-M1 through 10.1.57, 9.0.25 through 9.0.120, 8.5.46 through 8.5.100, 7.0.97 through 7.0.109
Timeline
- 2026-08-25: disclosed
- 2026-08-25: patched: Fixes released in versions 11.0.25, 10.1.58, and 9.0.121