CVE-1999-0832

Vulnerability

A buffer overflow vulnerability exists in the NFS server component of Linux, specifically in versions affected by the Red Hat Linux 4.2 and related releases. The flaw is triggered when processing a pathname that exceeds the buffer size, leading to memory corruption. The vulnerable code path is reachable during normal NFS operations where the server handles pathname arguments from RPC calls. The official description states that affects Linux NFS server and allows command execution via a long pathname [1].

Exploitation

An attacker can exploit this vulnerability by sending a crafted NFS RPC request containing an overly long pathname to a vulnerable Linux NFS server. The attacker must be able to send network traffic to the NFS service (typically on port 2049). No authentication is required, as the overflow occurs before any access control checks. The malicious pathname overflows a buffer, corrupting adjacent memory and enabling control over the execution flow.

Impact

Successful exploitation of this buffer overflow allows an attacker to execute arbitrary commands on the target system with the privileges of the NFS server process, typically root. This results in a complete compromise of the affected system, including full confidentiality, integrity, and availability impact.

Mitigation

Red Hat released an update for Red Hat Linux 4.2 that fixes this issue, as noted in the referenced advisory [1]. Affected users should apply the relevant vendor patch or update to a version that addresses the buffer overflow. No workarounds are documented in the available references.