CVE-2026-116497

A NULL pointer dereference vulnerability was found in gssproxy. When a GSSX_INIT_SEC_CONTEXT request is received with the target_name 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.

Red Hat has confirmed this vulnerability in gssproxy as shipped in Red Hat Enterprise Linux. The gssproxy daemon crashes when it receives a GSSX_INIT_SEC_CONTEXT request with the target_name field absent, due to a missing NULL pointer check. This can be triggered by any local user without authentication, causing a denial of service that persists until the daemon is manually restarted. Services that depend on gssproxy for Kerberos credential management, including NFS and IdM, are affected while the daemon is down.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

There is no way to fully mitigate this vulnerability without applying a code fix. The gssproxy Unix socket must be world-accessible for normal operation, and the default configuration accepts connections from any local user.

As a partial workaround, administrators can add "Restart=on-failure" to the gssproxy systemd unit to enable automatic restarts after a crash. This does not prevent the crash but limits the denial-of-service window. Note that a persistent attacker can still outpace the restart cycle.