-----BEGIN PGP SIGNED MESSAGE-----

______________________________________________________________________________

                        SUSE Security Announcement

        Package:                Linux Kernel (x86_64, AMD64)
        Announcement-ID:        SuSE-SA:2004:003
        Date:                   Monday, Jan 15th 2004 14:17 MET
        Affected products:      9.0
                                SuSE Linux Enterprise Server 8,
        Vulnerability Type:     local system compromise
        Severity (1-10):        6
        SUSE default package:   yes
        Cross References:

    Content of this advisory:
        1) security vulnerability resolved:
           - incorrect bounds checking in mremap()
           - inproper CPU register access check in 32bit ptrace()
           problem description, discussion, solution and upgrade information
        2) pending vulnerabilities, solutions, workarounds:
            - ethereal
            - mc
            - mod_gzip
            - tripwire
            - cvs
            - gnome-filesystem
            - XDM (XFree86, xf86)
            - 3ddiag
            - mod_auth_shadow
        3) standard appendix (further information)

______________________________________________________________________________

1)  problem description, brief discussion, solution, upgrade information

    The do_mremap() function of the Linux Kernel is used to manage
    (move, resize) Virtual Memory Areas (VMAs). By exploiting an incorrect
    bounds check in do_mremap() during the remapping of memory it is
    possible to create a VMA with the size of 0.
    In normal operation do_mremap() leaves a memory hole of one page and
    creates an additional VMA of two pages. In case of exploitation no
    hole is created but the new VMA has a 0 bytes length.
    The Linux Kernel's memory management is corrupted from this point
    and can be abused by local users to gain root privileges.
       Additionally Andi Kleen of SUSE LINUX found and fixed another bug
    in the 32bit emulation of ptrace() which allows to modify CPU registers    from user-space to get full access to system ressources.

    There is no temporary workaround for this bug.

    Please reboot your system to run the new kernel.


    AMD64 Platform:

    SuSE-9.0:
          4896825f6399bebc80073dbbd74432cd
    source rpm(s):
          e9afc5cbb5fc1dddb53e179a52d45f0a
          8b7667ac6baf4aebd4961274cbdaa84e
    source rpm(s):
          ffc25e3c1b9a4ed4e5182ff5cbdd5c18
          9422ec31eb76d26a1dfaca8fb8542907
    source rpm(s):
          8acc26621600cc7411f964656c435389

______________________________________________________________________________

2)  Pending vulnerabilities in SUSE Distributions and Workarounds:

    - ethereal
    Two remotely exploitable denial-of-service attacks were found in
    the network analyzer ethereal.
    New packages are available on our FTP servers.

    - mc
    By using a special combination of links in archive-files it is possible
    to execute arbitrary commands while mc tries to open it in its VFS.
    The packages will be released soon.

    - mod_gzip (apache-contrib)
    The apache module mod_gzip is vulnerable to remote code execution
    while running in debug-mode. We do not ship this module in debug-mode
    but future versions will include the fix.
    Additionally the mod_gzip code was audited to fix more possible security
    related bugs.
    After more testing a new apache-contrib RPM package will be released.

    - tripwire
    Tripwire is a file integrity checker. The tripwire version on SuSE Linux
    8.2 and 9.0 do crash when a requested file does not exists.
    New packages will be available soon.

    - cvs
    The cvs server-side can be tricked to create files in the root filesystem
    of the server by requesting malformed modules. The permissions on the
    root filesystem normally prevent this malfunction. Additionally the
    package will include a fix for a format-string bug.
    New packages are available on our FTP servers.

    - gnome-filesystem
    A script included in the gnome-filesystem package handles temporary
    files insecurely. This script is called by YaST2 with root
    privileges. The bug can be exploited locally to create or overwrite
    arbitrary files in the filesystem. The bug is fixed in our current
    source-tree since November 2003.
    New packages are available on our FTP servers.

    - XDM (XFree86, xf86)
    A missing check for failure conditions in the PAM code of XDM
    can lead to local root access in conjunction with Kerberos
    and alike. New packages will be released soon.

    - 3ddiag
    Some 3ddiag scripts handle temporary files in an insecure manner.
    Thanks to Stefan Nordhausen 
    for reporting some of the issues.
    New packages will be available on our FTP servers soon.

    - mod_auth_shadow (apache-contrib)
    This apache module ignores account expiration dates.
    The update will be released together with mod_gzip.

______________________________________________________________________________

3)  standard appendix: authenticity verification, additional information

  - Package authenticity verification:

    SUSE update packages are available on many mirror ftp servers all over
    the world. While this service is being considered valuable and important
    to the free and open source software community, many users wish to be
    sure about the origin of the package and its content before installing
    the package. There are two verification methods that can be used
    independently from each other to prove the authenticity of a downloaded
    file or rpm package:
    1) md5sums as provided in the (cryptographically signed) announcement.
    2) using the internal gpg signatures of the rpm package.

    1) execute the command
        md5sum 
       after you downloaded the file from a SUSE ftp server or its mirrors.
       Then, compare the resulting md5sum with the one that is listed in the
       announcement. Since the announcement containing the checksums is
       cryptographically signed (usually using the key security@suse.de),
       the checksums show proof of the authenticity of the package.
       We disrecommend to subscribe to security lists which cause the
       email message containing the announcement to be modified so that
       the signature does not match after transport through the mailing
       list software.
       Downsides: You must be able to verify the authenticity of the
       announcement in the first place. If RPM packages are being rebuilt
       and a new version of a package is published on the ftp server, all
       md5 sums for the files are useless.

    2) rpm package signatures provide an easy way to verify the authenticity
       of an rpm package. Use the command
        rpm -v --checksig 
       to verify the signature of the package, where  is the
       filename of the rpm package that you have downloaded. Of course,
       package authenticity verification can only target an un-installed rpm
       package file.
       Prerequisites:
        a) gpg is installed
        b) The package is signed using a certain key. The public part of this
           key must be installed by the gpg program in the directory
           ~/.gnupg/ under the user's home directory who performs the
           signature verification (usually root). You can import the key
           that is used by SUSE in rpm packages for SUSE Linux by saving
           this announcement to a file ("announcement.txt") and
           running the command (do "su -" to be root):
            gpg --batch; gpg < announcement.txt | gpg --import
           SUSE Linux distributions version 7.1 and thereafter install the
           key "build@suse.de" upon installation or upgrade, provided that
           the package gpg is installed. The file containing the public key
           is placed at the top-level directory of the first CD (pubring.gpg)
           and at ftp://ftp.suse.com/pub/suse/pubring.gpg-build.suse.de .


  - SUSE runs two security mailing lists to which any interested party may
    subscribe:

    suse-security@suse.com
        -   general/linux/SUSE security discussion.
            All SUSE security announcements are sent to this list.
            To subscribe, send an email to
                .

    suse-security-announce@suse.com
        -   SUSE's announce-only mailing list.
            Only SUSE's security announcements are sent to this list.
            To subscribe, send an email to
                .

    For general information or the frequently asked questions (faq)
    send mail to:
         or
         respectively.

    ====================================================================    SUSE's security contact is  or .
    The  public key is listed below.
    ====================================================================