CVE-2026-74909: Red Hat Build Of Keycloak 26.4

High severity, CVSS 8.1. EPSS: 0.8% chance of exploitation in the next 30 days.

Keycloak provides a policy enforcer to protect applications by matching incoming web requests against defined security policies. A flaw was found where the enforcer fails to correctly normalize web addresses that contain special encoded characters, such as those representing semicolons or directory traversal segments. An authenticated user can use these encoded characters to trick the enforcer into applying a less restrictive security policy than intended, potentially gaining unauthorized access to sensitive administrative or private application endpoints.

Affected products

• Red Hat Red Hat Build Of Keycloak 26.4: before 26.4.16-2 (fixed in 26.4.16-2); before 26.4-26 (fixed in 26.4-26)
• Red Hat Red Hat Build Of Keycloak 26.4.16
• Red Hat Red Hat Build Of Keycloak 26.6: before 26.6.7-3 (fixed in 26.6.7-3); before 26.6-20 (fixed in 26.6-20)
• Red Hat Red Hat Build Of Keycloak 26.6.7
• Red Hat Red Hat Single Sign-On 7

Published 2026-09-16. Last modified 2026-09-18.