CVE-2026-11800
HIGH
NVD
CVSS Score
8.1
Severity
HIGH
Published
Jun 25, 2026
Vendor
unknown
Description
A flaw was found in Keycloak. This JWT algorithm confusion vulnerability in the JWT Authorization Grant flow allows an attacker with valid client credentials to bypass signature verification. By forging an assertion, the attacker can create unauthorized access tokens. This enables the attacker to impersonate any federated user linked to the affected Identity Provider, leading to unauthorized access and potential privilege escalation.