SuSE Security Announcement

        Package:                kdenetwork
        Announcement-ID:        SuSE-SA:2002:042
        Date:                   Tue Nov 12 10:00:00 CET 2002
        Affected products:      7.2, 7.3
                                SuSE eMail Server III, 3.1
                                SuSE Firewall on CD
                                SuSE Linux Connectivity Server
                                SuSE Linux Enterprise Server 7
                                SuSE Linux Office Server
        Vulnerability Type:     remote command execution
        Severity (1-10):        6
        SuSE default package:   yes
        Cross References:        https://www.kde.org/info/security

    Content of this advisory:
        1) security vulnerability resolved: Remote command execution via
           the lisa lanbrowser.
           problem description, discussion, solution and upgrade information
        2) pending vulnerabilities, solutions, workarounds: problem in
           KDE rlogin:// URL handler
        3) standard appendix (further information)


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

    During a security review, the SuSE security team has found two
    vulnerabilities in the KDE lanbrowsing service.

    LISa is used to identify CIFS and other servers on the local
    network, and consists of two main modules: "lisa", a network daemon,
    and "reslisa", a restricted version of the lisa daemon.  LISa can
    be accessed in KDE using the URL type "lan://", and resLISa using
    the URL type "rlan://".

    LISA will obtain information on the local network by looking for
    an existing LISA server on other local hosts, and if there is one,
    it retrieves the list of servers from it.  If there is no other LISA
    server, it will scan the network itself.

    SuSE Linux can be configured to run the lisa daemon at system boot
    time. The daemon is not started by default, however.

    The first vulnerability found is a buffer overflow in the lisa
    daemon, and can be exploited by an attacker on the local network
    to obtain root privilege on a machine running the lisa daemon.
    It is not exploitable on a default installation of SuSE Linux,
    because the lisa daemon is not started by default.

    The second vulnerability is a buffer overflow in the lan:// URL
    handler. It can possibly be exploited by remote attackers to gain
    access to the victim user's account, for instance by causing the
    user to follow a bad lan:// link in a HTML document.

    This update provides fixes for SuSE Linux 7.2 and 7.3. Previous
    updates already corrected the vulnerability in SuSE Linux 8.0,
    and SuSE Linux 8.1 contains the fix already.

    Please download the update package for your distribution and verify its
    integrity by the methods listed in section 3) of this announcement.
    Then, install the package using the command "rpm -Fhv file.rpm" to apply
    the update.
    Our maintenance customers are being notified individually. The packages
    are being offered to install from the maintenance web.

    Intel i386 Platform:

    source rpm(s):

    source rpm(s):

    Sparc Platform:

    source rpm(s):

    PPC Power PC Platform:

    source rpm(s):


2)  Pending vulnerabilities in SuSE Distributions and Workarounds:

    In KDE 2.x and KDE 3.x, there is a vulnerability in the handler for
    rlogin:// URLs, which allows remote attackers to execute arbitrary
    shell commands with the privileges of the victim user. A similar
    vulnerability exists in KDE 2.x in the handler for telnet:// URLs.

    The SuSE KDE team is in the process of preparing a kdelibs update
    for SuSE Linux. In the interim, we recommend the to disable KDE
    support for rlogin as a workaround. On KDE 3.0, execute the following
    command as root:

         rm /opt/kde3/share/services/rlogin.protocol

    On KDE 2, execute these commands:

        rm /opt/kde2/share/services/rlogin.protocol
        rm /opt/kde2/share/services/telnet.protocol


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
       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 [email protected]),
       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.
        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 "[email protected]" 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

    [email protected]
        -   general/linux/SuSE security discussion.
            All SuSE security announcements are sent to this list.
            To subscribe, send an email to
                <[email protected]>.

    [email protected]
        -   SuSE's announce-only mailing list.
            Only SuSE's security announcements are sent to this list.
            To subscribe, send an email to
                <[email protected]>.

    For general information or the frequently asked questions (faq)
    send mail to:
        <suse-secu[email protected]> or
        <[email protected]> respectively.

    SuSE's security contact is <[email protected]> or <[email protected]>.
    The <[email protected]> public key is listed below.
    The information in this advisory may be distributed or reproduced,
    provided that the advisory is not modified in any way. In particular,
    it is desired that the clear-text signature shows proof of the
    authenticity of the text.
    SuSE Linux AG makes no warranties of any kind whatsoever with respect
    to the information contained in this security advisory.

Type Bits/KeyID    Date       User ID
pub  2048R/3D25D3D9 1999-03-06 SuSE Security Team <[email protected]>
pub  1024D/9C800ACA 2000-10-19 SuSE Package Signing Key <[email protected]>