CVE-2026-16093
Severity CVSS v4.0:
Pending analysis
Type:
Unavailable / Other
Publication date:
17/07/2026
Last modified:
17/07/2026
Description
Keycloak provides a mechanism called Client Policies to enforce security requirements on clients, such as requiring them to use signed JWTs for authentication. A flaw was discovered where this enforcement can be bypassed. An attacker with valid client credentials can provide a fake, unsigned assertion header that tricks the system into thinking the policy requirements have been met. This allows the attacker to authenticate using simpler methods like a client secret even when the administrator has mandated more secure, signed assertions.
Impact
Base Score 3.x
5.40
Severity 3.x
MEDIUM