CVE-2026-16093 Auth bypass in Red Hat Data Grid 8
Attackers with valid credentials can bypass signed JWT policies by sending unsigned headers, allowing authentication via weaker client secret methods.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-16093?
CVE-2026-16093 is a medium-severity authentication bypass vulnerability in Redhat Build of Keycloak, published on 17 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-807
Which versions are affected by CVE-2026-16093?
1 open source package ship an affected version, including keycloak. It affects 4 products.
| Package | Affected | Fixed in |
|---|---|---|
keycloak Bitnami | All versions | 26.7.3 |
Products include Redhat Build of Keycloak, Redhat Data Grid, Redhat Jboss Enterprise Application Platform Expansion Pack, Redhat Single Sign-On.
How do I fix CVE-2026-16093?
Upgrade keycloak to 26.7.3 or later.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-16093 being exploited?
There is no known exploitation of CVE-2026-16093 in the wild and no public exploit code.
Other vulnerabilities in Redhat Build of Keycloak
- CVE-2026-15572 Keycloak-services: keycloak-services: dcr protocol mapper type-swap policy bypass allows privilege escalation
- CVE-2026-3047 Keycloak SAML Broken has Authentication Bypass by Primary Weakness
- CVE-2026-15573 Keycloak-services: keycloak-services: authorization bypass via unnormalized uri matching in pathmatcher
- CVE-2026-16102 Keycloak-services: keycloak-services: default dcr policy allows role forgery via user property mappers
- CVE-2026-1609 Org.keycloak/keycloak-quarkus-server: keycloak: unauthorized access via jwt authorization grant with disabled users
Sources
Also known as BIT-keycloak-2026-16093, CLEANSTART-2026-AH74122, GHSA-jmhg-9c54-p575.