Linux Kernel SUNRPC Memory Leak Vulnerability in GSS Proxy Authentication

A vulnerability in the Linux kernel's SUNRPC implementation can lead to a memory leak of netobj data when the function gss_read_proxy_verf() encounters an error. This issue arises during server-side RPCGSS authentication, where the GSS proxy upcall is used. The vulnerability has been addressed in the official Linux stable releases.

Impact

Exploitation of this vulnerability can cause a memory leak, potentially leading to increased memory usage and degradation of system performance.

Reproduction

The vulnerability can be reproduced by triggering a failure in the gss_read_proxy_verf() function while using GSS proxy authentication in an RPC context. This can be done by sending a request that causes the function to deny access, such as one that exceeds the expected input length. The function will then improperly handle the error, leading to a memory leak of netobj data.

Remediation

Users can upgrade to the latest version of the Linux kernel to address this vulnerability.