Ludwig Nussel discovered that kdm, the X display manager for KDE, handles access to the session type configuration file insecurely, which may lead to the disclosure of arbitrary files through a symlink attack.
For the stable distribution (sarge) this problem has been fixed in version 3.3.2-1sarge3.
For the unstable distribution (sid) this problem has been fixed in version 3.5.2-2.
We recommend that you upgrade your kdm package.
MD5 checksums of the listed files are available in the original advisory.