A NULL pointer dereference vulnerability was found in gssproxy. When a GSSXINITSECCONTEXT request is received with the targetname field absent, the daemon dereferences the resulting NULL pointer and crashes. The request requires no authentication, allowing any local user to crash the gssproxy daemon via its Unix socket. The daemon does not automatically restart, resulting in a persistent denial of service that also affects dependent services such as Kerberized NFS and IdM.