KDM: Symlink vulnerability

Background

KDE is a feature-rich graphical desktop environment for Linux and Unix-like Operating Systems. KDM is the KDE Display Manager and is part of the kdebase package.

Description

Ludwig Nussel discovered that KDM could be tricked into allowing users to read files that would otherwise not be readable.

Impact

A local attacker could exploit this issue to obtain potentially sensitive information that is usually not accessable to the local user such as shadow files or other user’s files. The default Gentoo user running KDM is root and, as a result, the local attacker can read any file.

Workaround

There is no known workaround at this time.

Resolution

All kdebase users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose kde-base/kdebase

All KDE split ebuild users should upgrade to the latest KDM version:

 # emerge --sync
 # emerge --ask --oneshot --verbose kde-base/kdm