A memory leak flaw was found in cockpit-ws. The login page handler leaks a heap allocation on every unauthenticated request that carries a CockpitLang cookie, allowing a remote unauthenticated attacker to exhaust memory on the host and cause a denial of service.
Restrict network access to the cockpit port to trusted clients until a fix is available. No configuration-level mitigation removes the flaw entirely, since the login page must remain reachable without authentication.