CVE Vulnerabilities


Improper Link Resolution Before File Access ('Link Following')

Published: Apr 17, 2014 | Modified: May 05, 2014
CVSS 3.x
CVSS 2.x
1.9 LOW

DistUpgrade/ in Update Manager before 1:, 1:0.134.x before 1:, 1:0.142.x before 1:, 1:0.150.x before 1:, and 1:0.152.x before 1: does not properly create temporary files, which allows local users to obtain the XAUTHORITY file content for a user via a symlink attack on the temporary file.


The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

Affected Software

Name Vendor Start Version End Version
Ubuntu_linux Canonical 10.10 10.10
Ubuntu_linux Canonical 8.04 8.04
Ubuntu_linux Canonical 11.04 11.04
Update-manager Canonical 1:0.152.25 1:0.152.25
Ubuntu_linux Canonical 11.10 11.10
Update-manager Canonical * 1:0.87.24
Update-manager Canonical 1:0.134.7 1:0.134.7
Update-manager Canonical 1:0.142.19 1:0.142.19
Update-manager Canonical 1:0.150 1:0.150
Ubuntu_linux Canonical 10.04 10.04

Potential Mitigations

  • Follow the principle of least privilege when assigning access rights to entities in a software system.
  • Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.