A flaw was found in the theme localization endpoints of the keycloak-services component, which is the core service responsible for authentication flows and theme management in Keycloak. The issue occurs because the system accepts arbitrary locale tags from unauthenticated requests and stores them in a permanent in-memory cache without limits. An attacker can exploit this by sending a large number of unique locale tags, eventually causing the server to run out of memory and crash.

A flaw was found in the theme localization endpoints of the keycloak-services component, which is the core service responsible for authentication flows and theme management in Keycloak. The issue occurs because the system accepts arbitrary locale tags from unauthenticated requests and stores them in a permanent in-memory cache without limits. An attacker can exploit this by sending a large number of unique locale tags, eventually causing the server to run out of memory and crash.

keycloak-services: keycloak-services: Privilege escalation via impersonation role allows takeover of realm administrator accounts keycloak-services: keycloak-services: SAML Redirect DEFLATE helpers leak native zlib state keycloak-services: keycloak-services: Broker-originated username collision causes account lockout keycloak-services: keycloak-services: Incomplete fix for arbitrary filesystem path probing via keystore parameters io.netty/netty-handler: Netty: TLS hostname verification bypass via OpenSSL client path misconfiguration keycloak-services: keycloak-services: Incomplete fix for CVE-2026-15573 allows policy enforcer bypass via percent-encoded URI segments keycloak-services: keycloak-services: unauthenticated DoS via unbounded locale caching

Ein Angreifer kann mehrere Schwachstellen in Keycloak ausnutzen, um Sicherheitsvorkehrungen zu umgehen, um seine Privilegien zu erhöhen, um einen Denial of Service Angriff durchzuführen und um Informationen offenzulegen.