Pulseaudio: Privilege escalation

Background

Pulseaudio is a networked sound server with an advanced plugin system.

Description

Marcus Meissner from SUSE reported that the pa_drop_root() function does not properly check the return value of the system calls setuid(), seteuid(), setresuid() and setreuid() when dropping its privileges.

Impact

A local attacker could cause a resource exhaustion to make the system calls fail, which would cause Pulseaudio to run as root. The attacker could then perform actions with root privileges.

Workaround

There is no known workaround at this time.

Resolution

All Pulseaudio users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=media-sound/pulseaudio-0.9.9"