CVE-2026-4630: Keycloak: keycloak: unauthorized resource access and data modification via insecure direct object reference

A flaw was found in Keycloak. An authenticated client could exploit an Insecure Direct Object Reference (IDOR) vulnerability in the Authorization Services Protection API endpoint. By knowing or obtaining a resource's unique identifier (UUID) belonging to another Resource Server within the same realm, the client could bypass authorization checks. This allows the client to perform unauthorized GET, PUT, and DELETE operations on resources, leading to information disclosure and potential unauthorized modification or deletion of data.