CVE-2026-16093

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.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-16093	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2501729	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:redhat:build_of_keycloak:-::::-:::
	cpe:2.3:a:redhat:data_grid:8.0:::::::*
	cpe:2.3:a:redhat:jboss_enterprise_application_platform_expansion_pack:-:::::::*
	cpe:2.3:a:redhat:single_sign-on:7.0:::::::*

History

No history.

Information

Published : 2026-07-17 17:17

Updated : 2026-08-09 15:04

NVD link : CVE-2026-16093

Mitre link : CVE-2026-16093

CVE.ORG link : CVE-2026-16093

JSON object : View

Products Affected

redhat

build_of_keycloak
single_sign-on
data_grid
jboss_enterprise_application_platform_expansion_pack

CWE

CWE-807

Reliance on Untrusted Inputs in a Security Decision

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