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SuSE Security Announcement: miscellaneous

Nov 15, 2000, 20:37 (0 Talkback[s])
(Other stories by Roman Drahtmüller)

Date: Wed, 15 Nov 2000 15:36:30 +0100 (MET)
From: Roman Drahtmueller draht@suse.de
To: suse-security-announce@suse.de
Subject: [suse-security-announce] SuSE: miscellaneous

SuSE: miscellaneous 15:30 MET, Wednesday, November 15 2000

This notice addresses the latest security advisories from various Linux vendors as well as private contributors on public security forums. The issues have been collected to keep the noise on the public security forums at a reduced level.

The information herein should be considered both background as well as upgrade information (please read carefully).

        1) SuSE security staff

        2) packages:
                gpg     (update information)
                bind8   (status: update avail, announcement pending)
                pine    (status: testing new version 4.30)
                dump    (status: not vulnerable)
                phf     (status: not vulnerable)
                gs      (status: pending)
                global  (status: building)
                crontab (status: not vulnerable)
                vlock   (status: not vulnerable)
                tcpdump (status: update avail, testing)
                tcsh    (status: update+announcement pending)
                modules (status: more updates for older distributions)
1) SuSE security staff

SuSE welcomes security professional Sebastian Krahmer aboard the SuSE security team. His name has already been on top of the last SuSE security announcement about the security problems in the modules package. Enlarging the capacity of the security team, Sebastian will be busy fixing security problems, auditing code and maintaining security- related software. More security announcements from him will be seen in the future.

2) packages

* gpg

GnuPG may erroneously recognize a file/mail to be correctly signed, if there are multiple signatures and the file/mail has been modified. This bug affects all GnuPG versions prior to and including 1.0.3. It has been fixed in version 1.0.4. Updated packages are available on our German ftp server (as well as its mirrors) for the SuSE distributions 6.3, 6.4 and 7.0. Please note that the gpg packages for the SuSE-7.0 distribution have an addon, called gpgaddon. It contains implementations of cipher algorythms that require licenses in many countries due to software patents. Those gpgaddon packages are not listed below.
There will not be a security announcement for this package - the privacy risk for users of the old package is considerably small. You can update your installed packages using the command
rpm -Uhv
where is one of the following FTP URLs to chose from.

Please use the SuSE Linux mirrors as listed at
http://www.suse.de/de/support/download/ftp/inland.html .

The md5sums for the files on the ftp server are:

i386 Intel Platform

source rpm:

source rpm:

source rpm:

Sparc Platform

source rpm:

PPC Power PC platform

source rpm:

source rpm:

AXP Alpha Platform

source rpm:

source rpm:

* bind8

BIND, the Berkeley Internet Name Daemon, versions before 8.2.2p7, has been found vulnerable to two denial of service attacks: named may crash after a compressed zone transfer request and if an SRV record (defined in RFC2782) is sent to the server. SuSE versions 6.0 through 6.4 are affected by this problem. The bind8 package in SuSE-7.0 is not susceptible to the problems because a different version of bind8 has been used in this distribution.

A temporary workaround against the first error is to disable zone transfers if those are not needed (it is recommended for security reasons, and the default configuration in our package has zone transfers disabled.). Since the second bug can't be circumvented so easily, it is recommended to upgrade the bind8 package as soon as possible. Recognizing the urgency of this issue, the updated packages are on their way to the ftp server right now. An announcement covering the issue will follow this notice.

* pine

The popular text-based mail user agent is vulnerable to a buffer overflow in the portion of code that periodically checks for the arrival of new mail. In addition, there is an error in the header parsing code which could lead to a crash of the mail program. The authors of pine (University of Washington, Seattle, see http://www.washington.edu/pine/credits.html) have published a new version of the pine package that should fix the known problems. During testing, several instabilities of the program have been observed so that we have delayed the release of the updated version. Additional patches are being tested right now so that the release of the new version 4.30 can be expected within days.

* dump

The Linux implementation of the ext2fs backup utility "dump" can be tricked into running arbitrary commands as root in case it is installed setuid root. dump is not installed suid root in SuSE Linux releases 6.0 through (the most recent) 7.0 because there is no convincing reason to do so. Therefore, SuSE Linux is not vulnerable to this problem with the dump program.

* phf cgi program

proton proton@ENERGYMECH.NET has discovered a buffer overflow that can lead the phf cgi program to execute arbitrary code with the privileges of the user that the webserver is running under. SuSE distributions contain a cgi program that is called phf, it is included in the thttpd package. Installed under /usr/local/httpd/htdocs/cgi-bin/phf, this program is a booby trap that logs attackers intending to exploit formerly known bugs of the phf program. By consequence, SuSE distributions are not vulnerable to the buffer overflow in the phf program.

* gs

The Ghostscript program in SuSE distributions runtime-links against shared libraries in the current working directory if a shared library with the adequate name is present. The problem is created by exporting the environment variable LD_RUN_PATH at linking time during the package compile process. Later, at runtime linking, the runtime linker ld-linux.so.2 will try to open ./libc.so.6. If this fails, the linker will continue searching the usual paths to find the library. Basically, this means that users should call gs as well as all programs using gs (such as gv or ghostview) in a directory that is only writeable by the user calling gs. It is expected that more Linux distributions (other than SuSE Linux) and possibly commercial unix vendors as well are affected by this problem. In future versions of the SuSE Linux distribution, this problem will be fixed.

* global

htags, one program within the global package, is a hypertext generator from C, Yacc and Java source code. The "-f" option generates a cgi script as an input form backend that is vulnerable to a simple remote attack if the script is executable by a webserver. Remote attackers can run arbitrary commands under the user privileges of the webserver. The global package is not installed per default, nor is the bug present in the "installed-only" state of the package. However, if you use the program and the "-f" option of htags, it is recommended to upgrade the package as soon as possible. We are working on the update packages.

* crontab

A tmp file vulnerability has been found in various implementations of the crontab(1) command. SuSE Linux is not affected by this problem.

* vlock

vlock is a terminal locking program for the Linux virtual system console. It has been reported by Bartlomiej Grzybicki that it is possible to crash a running vlock and thus giving access to a console without a password. However, the conditions under which the failure happens are not clear. SuSE distributions are not concerned because the vlock program is not included in the distribution.

* tcpdump

Several buffer overflows have been found in the tcpdump program, a network analysis program, according to FreeBSD Security Advisory FreeBSD-SA-00:61.tcpdump. The vulnerability can be used to remotely crash a running tcpdump program. Since the version of tcpdump included in SuSE distributions is not capable of decoding AFS ACL packets, this particular part of the bugs does not concern SuSE Linux. Though, some intrusion detection systems rely on tcpdump's output so that a proper operation of the tcpdump program is crutial. There are updates packages available for download on our ftp server which fix the vulnerability. The security announcement is pending while we're still testing the packages.

* tcsh

proton has found a temporary file vulnerability in the portion of code in the tcsh that handles redirects of the form

        cat << END_OF_TEXT
With this vulnerability in place, it is possible for an attacker to overwrite arbitrary files with the privileges of the user of tcsh. There is no fix for this problem other than an upgrade to a fixed version which will be available on our ftp server shortly. An advisory covering this matter will follow.

* modules/modutils

Sebastian Krahmer has issued a SuSE security announcement about the shell meta character expansion vulnerability in the modprobe program that is responsible for the automatic loading of kernel modules upon request. In addition to the update packages for the vulnerable versions of the SuSE distribution, we will provide updates for the older distributions (6.0-6.3) shortly, even though these distributions have not been found vulnerable to the modprobe problem. The rpm packages can be found at the usual location shortly.

Roman Drahtmüller.
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| Roman Drahtmüller        draht@suse.de //          "Caution: Cape does |
  SuSE GmbH - Security           Phone: //       not enable user to fly."
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