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Red Hat Security Advisory: syslog format vulnerability in klogd

Date: Mon, 18 Sep 2000 15:42:00 -0400
From: [email protected]
To: [email protected]
Subject: [RHSA-2000:061-02] syslog format vulnerability in
klogd


                   Red Hat, Inc. Security Advisory

Synopsis:          syslog format vulnerability in klogd
Advisory ID:       RHSA-2000:061-02
Issue date:        2000-09-18
Updated on:        2000-09-18
Product:           Red Hat Linux
Keywords:          syslog format string klogd syslogd
Cross references:  N/A

1. Topic:

Various vulnerabilities exist in syslogd/klogd. By exploiting
these vulnerabilities, it could be possible for local users to gain
root access. No remote exploit exists at this time, but it remains
theoretically possible that this vulnerability could be exploited
remotely under certain rare circumstances.

All users should upgrade to the new sysklogd packages. Users of
Red Hat Linux 6.0 and 6.1 should use the packages for Red Hat Linux
6.2.

2. Relevant releases/architectures:

Red Hat Linux 5.2 – i386, alpha, sparc
Red Hat Linux 6.0 – i386, alpha, sparc
Red Hat Linux 6.1 – i386, alpha, sparc
Red Hat Linux 6.2 – i386, alpha, sparc

3. Problem description:

klogd contains instances of the:

    syslog( LOG_INFO, buffer );

vulnerability that has been recently been discussed on Bugtraq and
similar mailing lists; by supplying some string that contains ‘%’
escapes, it is possible to have those escapes interpreted, which
can lead to the ability to gain root access.

Also, there are a couple of minor buffer overflow/termination
problems that could allow local users to crash syslogd and cause
bogus messages to be printed on the local system console.

The updated sysklogd packages fix these
vulnerabilities/issues.

4. Solution:

For each RPM for your particular architecture, run:

rpm -Fvh [filename]

where filename is the name of the RPM.

5. Bug IDs fixed (http://bugzilla.redhat.com/bugzilla
for more info):

N/A

6. RPMs required:

Red Hat Linux 5.2:

sparc:
ftp://updates.redhat.com/5.2/sparc/sysklogd-1.3.31-1.6.sparc.rpm

alpha:
ftp://updates.redhat.com/5.2/alpha/sysklogd-1.3.31-1.6.alpha.rpm

i386:
ftp://updates.redhat.com/5.2/i386/sysklogd-1.3.31-1.6.i386.rpm

sources:
ftp://updates.redhat.com/5.2/SRPMS/sysklogd-1.3.31-1.6.src.rpm

Red Hat Linux 6.2:

sparc:
ftp://updates.redhat.com/6.2/sparc/sysklogd-1.3.31-17.sparc.rpm

i386:
ftp://updates.redhat.com/6.2/i386/sysklogd-1.3.31-17.i386.rpm

alpha:
ftp://updates.redhat.com/6.2/alpha/sysklogd-1.3.31-17.alpha.rpm

sources:
ftp://updates.redhat.com/6.2/SRPMS/sysklogd-1.3.31-17.src.rpm

7. Verification:

MD5 sum                           Package Name

cd92613fc9a7409a90f6ff774e6e85d7 5.2/SRPMS/sysklogd-1.3.31-1.6.src.rpm
c7c44b7a38f4518daecca77cf7d45ba8 5.2/alpha/sysklogd-1.3.31-1.6.alpha.rpm
f100359030451c4be9b3bd99c3ec73a1 5.2/i386/sysklogd-1.3.31-1.6.i386.rpm
1c7f004ca29c966e0a03896f239d1317 5.2/sparc/sysklogd-1.3.31-1.6.sparc.rpm
69d50a8a9d490598fc11eef40fdf4552 6.2/SRPMS/sysklogd-1.3.31-17.src.rpm
2a7e2c7848d1f2d9607f3e6e3702cf2e 6.2/alpha/sysklogd-1.3.31-17.alpha.rpm
287d5022aa9d1a6ba9e03c51acc85229 6.2/i386/sysklogd-1.3.31-17.i386.rpm
150a05567dd4d626326028b1ac31f34d 6.2/sparc/sysklogd-1.3.31-17.sparc.rpm

These packages are GPG signed by Red Hat, Inc. for security. Our
key is available at:
http://www.redhat.com/corp/contact.html

You can verify each package with the following command:
rpm –checksig <filename>

If you only wish to verify that each package has not been
corrupted or tampered with, examine only the md5sum with the
following command:
rpm –checksig –nogpg <filename>

8. References:

Thanks go to Jouko Pynnonen, Solar Designer, and Daniel
Jacobowitz for discovering the vulnerabilities and providing
patches.

Copyright(c) 2000 Red Hat, Inc.