Multiple Linux Vendor rpc.statd Remote Format String Vulnerability
A vulnerability exists in the 'rpc.statd' program, which is part of the 'nfs-utils' package that is shipped with a number of popular Linux distributions. Because of a format-string vulnerability when calling the 'syslog()' function, a remote attacker can execute code as root.
The 'rpc.statd' server is an RPC server that implements the Network Status and Monitor RPC protocol. It's a component of the Network File System (NFS) architecture.
The logging code in 'rpc.statd' uses the 'syslog()' function, passing it as the format string user-supplied data. A malicious user can construct a format string that injects executable code into the process address space and overwrites a function's return address, thus forcing the program to execute the code.
The 'rpc.statd' server requires root privileges for opening its network socket, but fails to drop these privileges later on. Therefore, code run by the malicious user will execute with root privileges.
Debian, Red Hat, and Connectiva have all released advisories. Presumably, any Linux distribution that runs the statd process is vulnerable unless patched for the problem.