8.1 High

Keycloak vulnerable to authorization bypass via incorrect uri comparison

CVE-2026-9800

Description A flaw was found in Keycloak Policy Enforcer. This vulnerability allows any authenticated user to bypass all authorization policies, including role, scope, and User-Managed Access (UMA) permission checks. By including the configured access-denied page path within a request URL, either as a path segment or a query parameter, an attacker can gain unauthorized access to protected resources.

Assessment

CVSS: 8.1 (v3.1)
Severity: High
EPSS: 0.00651% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 29 October 2026
Last updated: 29 October 2026
Affected: maven · org.keycloak:keycloak-services, org.keycloak:keycloak-policy-enforcer
Weakness: CWE-1025

CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

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