Description (CNA)
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.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Red Hat / Red Hat build of Keycloak 26.6 | unaffected 26.6.7-3 before * |
| Red Hat / Red Hat build of Keycloak 26.6 | unaffected 26.6-20 before * |
| Red Hat / Red Hat build of Keycloak 26.6 | unaffected 26.6-20 before * |
| Red Hat / Red Hat build of Keycloak 26.6.7 | unaffected |
| Red Hat / Red Hat build of Keycloak 26.6.7 | unaffected |
| Red Hat / Red Hat build of Keycloak 26.6.7 | unaffected |
| Red Hat / Red Hat Data Grid 8 | affected |
| Red Hat / Red Hat JBoss Enterprise Application Platform Expansion Pack | affected |
| Red Hat / Red Hat Single Sign-On 7 | affected |
CWE
CWE-807
References
- https://access.redhat.com/errata/RHSA-2026:68277
- https://access.redhat.com/errata/RHSA-2026:68278
- https://access.redhat.com/security/cve/CVE-2026-16093
- https://bugzilla.redhat.com/show_bug.cgi?id=2501729
ADP enrichment
No English description supplied.
No references supplied.