GDM could be made to launch a browser and leak information about the system.
Henne Vogelsang discovered that under certain PolicyKit configurations, GDM could be made to launch a browser. A local attacker could exploit this to gain access to files with the privileges of the gdm user. PolicyKit is not configured in this manner in Ubuntu by default.
1 June 2011
A security issue affects these releases of Ubuntu and its derivatives:
GDM could be made to launch a browser and leak information about the system.
Henne Vogelsang discovered that under certain PolicyKit configurations, GDM could be made to launch a browser. A local attacker could exploit this to gain access to files with the privileges of the gdm user. PolicyKit is not configured in this manner in Ubuntu by default.
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.
After a standard system update you need to reboot your computer to make all the necessary changes.
Vulmon