Ubuntu: 1950-1: Light Display Manager vulnerability
Posted by Benjamin D. Thomas   
Ubuntu Light Display Manager could be made to expose sensitive information.
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Ubuntu Security Notice USN-1950-1
September 12, 2013

lightdm vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 13.04

Summary:

Light Display Manager could be made to expose sensitive information.

Software Description:
- lightdm: Display Manager

Details:

It was discovered that Light Display Manager created .Xauthority files with
incorrect permissions. A local attacker could use this flaw to bypass
access restrictions.

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 13.04:
  lightdm                         1.6.0-0ubuntu3.1

After a standard system update you need to reboot your computer to make
all the necessary changes.

References:
  http://www.ubuntu.com/usn/usn-1950-1
  CVE-2013-4331

Package Information:
  https://launchpad.net/ubuntu/+source/lightdm/1.6.0-0ubuntu3.1