Bug 2517354 (CVE-2026-74909) - CVE-2026-74909 keycloak-services: keycloak-services: Incomplete fix for CVE-2026-15573 allows policy enforcer bypass via percent-encoded URI segments
Summary: CVE-2026-74909 keycloak-services: keycloak-services: Incomplete fix for CVE-2...
Keywords:
Status: NEW
Alias: CVE-2026-74909
Deadline: 2026-11-09
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-08-17 10:51 UTC by OSIDB Bzimport
Modified: 2026-09-16 13:33 UTC (History)
11 users (show)

Fixed In Version:
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Description OSIDB Bzimport 2026-08-17 10:51:56 UTC
An incomplete fix for CVE-2026-15573 in Keycloak PathMatcher allows an authenticated attacker to bypass authorization policies. The original fix introduced URI normalization to strip matrix parameters and resolve dot segments, but this cleanup occurs before percent-decoding. Consequently, percent-encoded semicolons (percent-3B) and percent-encoded dot segments (percent-2Epercent-2E) bypass the normalization logic. When the Keycloak policy enforcer is used with a servlet container that decodes these characters during routing (such as Tomcat or WildFly), the enforcer matches the request against a permissive catch-all resource while the container routes the request to a restricted endpoint. This allows a low-privilege user to access protected resources that should be denied by the configured policy.


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