CVE-2026-120984

Summary

A session attribute cleanup flaw in Keycloak's client management component allows authenticated attackers with client management permissions to bypass authorization controls by persisting a malicious JavaScript policy. This policy executes server-side during authorization requests, enabling arbitrary code execution.

Exploitability

Exploitation requires authenticated access with client management permissions and knowledge of the internal session attribute handling flaw; no public exploit exists.

Blast radius

Successful exploitation grants full server compromise, including read/write access to all realm data, user credentials, and administrative functions via arbitrary code execution.

Detection

No reliable host or network indicator is derivable from the published description.

Prioritized remediation

Upgrade to Keycloak 25.0.4 or later, as this version includes the fix for improper session attribute cleanup in client authorization setup (CVE-2026-120984).

Analysis generated locally by garnet-coder (no data left the box). AI-assisted — verify against primary sources before acting.