CVE-2026-4634

Name of the Vulnerable Software and Affected Versions Keycloak (affected versions not specified)

Description A flaw exists in Keycloak where an unauthenticated attacker can cause a Denial of Service (DoS) by sending a crafted POST request to the OpenID Connect (OIDC) token endpoint. The attack involves an excessively long scope parameter. This leads to high resource consumption and prolonged processing times.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.