[KDE Security Advisory] KDM symlink attack vulnerability

[Dirk Mueller <mueller () kde org>]

KDE Security Advisory: KDM symlink attack vulnerability
Original Release Date: 2006-06-14
URL: http://www.kde.org/info/security/advisory-20060614-1.txt

0. References

        CVE-2006-2449


1. Systems affected:

        KDM as shipped with KDE 3.2.0 up to including 3.5.3. KDE 3.1.x and
        older and newer versions than KDE 3.5.3 are not affected. 


2. Overview:

        KDM allows the user to select the session type for login. This
        setting is permanently stored in the user home directory. By
        using a symlink attack, KDM can be tricked into allowing the
        user to read file content that would otherwise be unreadable
        to this particular user. This vulnerability was discovered
        and reported by Ludwig Nussel.
       

3. Impact:

        KDM might allow a normal user to read the content of /etc/shadow
        or other files, which allows compromising the privacy of another
        user or even the security of the whole system.

4. Solution:

        Source code patches have been made available which fix these
        vulnerabilities. Contact your OS vendor / binary package provider
        for information about how to obtain updated binary packages.


5. Patch:

        A patch for KDE 3.4.0 - KDE 3.5.3 is available from
        ftp://ftp.kde.org/pub/kde/security_patches :

        9daecff07d57dabba35da247e752916a  post-3.5.0-kdebase-kdm.diff

        A patch for KDE 3.3.x is available from
        ftp://ftp.kde.org/pub/kde/security_patches :

        f2e1424d97f2cd18674bef833274c5e3  post-3.3.0-kdebase-kdm.diff

        A patch for KDE 3.2.x is available from
        ftp://ftp.kde.org/pub/kde/security_patches :

        8aa6b41cccca4216c6eb1cf705c2370a  post-3.2.0-kdebase-kdm.diff