Paul Szabo discovered a race condition in login. While setting up tty permissions, login did not correctly handle symlinks. If a local attacker were able to gain control of the system utmp file, they could cause login to change the ownership and permissions on arbitrary files, leading to a root privilege escalation.
The problem can be corrected by updating your system to the following package versions:
18 December 2008
A security issue affects these releases of Ubuntu and its derivatives:
Paul Szabo discovered a race condition in login. While setting up tty permissions, login did not correctly handle symlinks. If a local attacker were able to gain control of the system utmp file, they could cause login to change the ownership and permissions on arbitrary files, leading to a root privilege escalation.
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system upgrade is sufficient to effect the necessary changes.
Vulmon