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Home » Hacking News » RedHat RHSA-2003:032-01: tcpdump DoS

RedHat RHSA-2003:032-01: tcpdump DoS

by Nikola Strahija on April 24th, 2003 A vulnerability has been found in tcpdump package which, if exploited, could lead to denial-of-service attack and could allow arbitrary code execution.

Red Hat Security Advisory

Synopsis: Updated tcpdump packages fix various vulnerabilities
Advisory ID: RHSA-2003:032-01
Issue date: 2003-04-23
Updated on: 2003-04-23
Product: Red Hat Linux
Cross references:
Obsoletes: RHSA-2002:094
CVE Names: CAN-2002-1350 CAN-2003-0093 CAN-2003-0108 CAN-2003-0145

1. Topic:

Updated tcpdump, libpcap, and arpwatch packages are available, fixing
a number of vulnerabilities that could be used to cause a denial of service
attack, or possibly execute arbitrary code.

2. Relevant releases/architectures:

Red Hat Linux 7.1 - i386
Red Hat Linux 7.2 - i386, ia64
Red Hat Linux 7.3 - i386
Red Hat Linux 8.0 - i386

3. Problem description:

tcpdump is a command-line tool for monitoring network traffic.

The BGP decoding routines in tcpdump before 3.6.2 used incorrect bounds
checking when copying data, which allows remote attackers to cause a denial
of service and possibly execute arbitrary code (as the 'pcap' user).

The RADIUS decoder in tcpdump 3.6.2 and earlier allows remote attackers to
cause a denial of service (crash) via an invalid RADIUS packet with a
header length field of 0. This causes tcpdump to generate data within an
infinite loop.

A vulnerability in tcpdump before 3.7.2 is related to an inability to
handle unknown RADIUS attributes properly, and allows remote attackers to
cause a denial of service (infinite loop).

The ISAKMP parser in tcpdump 3.6 through 3.7.1 allows remote attackers to
cause a denial of service (CPU consumption) via a malformed ISAKMP
packet to UDP port 500, causing tcpdump to enter an infinite loop.

Users of tcpdump are advised to upgrade to these errata packages, which
contain patches to correct these issues.

4. Solution:

Before applying this update, make sure all previously released errata
relevant to your system have been applied.

To update all RPMs for your particular architecture, run:

rpm -Fvh [filenames]

where [filenames] is a list of the RPMs you wish to upgrade. Only those
RPMs which are currently installed will be updated. Those RPMs which are
not installed but included in the list will not be updated. Note that you
can also use wildcards (*.rpm) if your current directory *only* contains the
desired RPMs.

Please note that this update is also available via Red Hat Network. Many
people find this an easier way to apply updates. To use Red Hat Network,
launch the Red Hat Update Agent with the following command:


This will start an interactive process that will result in the appropriate
RPMs being upgraded on your system.

5. RPMs required:

Red Hat Linux 7.1:



Red Hat Linux 7.2:




Red Hat Linux 7.3:



Red Hat Linux 8.0:



6. Verification:

MD5 sum Package Name
292d708f1fb450602bee21df6156d893 7.1/en/os/SRPMS/tcpdump-3.6.3-
5bcf5cc77482fc13c344c27a19686ac1 7.1/en/os/i386/arpwatch-2.1a11-
b21e20256a1d1cfa53fdb462c8f90c4b 7.1/en/os/i386/libpcap-0.6.2-
98718feffb84ef3fcfea62ed23db17fc 7.1/en/os/i386/tcpdump-3.6.3-
f8672f45e55ffde6ded3c0d7d01472b1 7.2/en/os/SRPMS/tcpdump-3.6.3-
1be989e664e3041974c851a20455fd44 7.2/en/os/i386/arpwatch-2.1a11-
56b816371fd291638958b95d77c323c9 7.2/en/os/i386/libpcap-0.6.2-
652218eb2d907bfd6e26db476777d2fc 7.2/en/os/i386/tcpdump-3.6.3-
a24c92995de53d152ed772e598258ef8 7.2/en/os/ia64/arpwatch-2.1a11-
6ef27041aeed8dbfdf01b1370043b883 7.2/en/os/ia64/libpcap-0.6.2-
c8dcd70b27bdaed019f0e9d599cdfe67 7.2/en/os/ia64/tcpdump-3.6.3-
684e881a536069527f0396e8e0108b6e 7.3/en/os/SRPMS/tcpdump-3.6.3-
c806db970d9eb13200e1883ef01bc331 7.3/en/os/i386/arpwatch-2.1a11-
1e84890cbeee2a0be5a63008a46f3485 7.3/en/os/i386/libpcap-0.6.2-
3ce86622d68cb02d8b7b7c0f6e7068bd 7.3/en/os/i386/tcpdump-3.6.3-
c8324dcde1d5c01f0089f6519a2e79b9 8.0/en/os/SRPMS/tcpdump-3.6.3-
a9d325e68611a1f4d8d33684fdecd886 8.0/en/os/i386/arpwatch-2.1a11-
343ddd0c76865727ffa4c9daac3015ba 8.0/en/os/i386/libpcap-0.6.2-
c5bc01690d6592889741cc8a213da2f2 8.0/en/os/i386/tcpdump-3.6.3-

These packages are GPG signed by Red Hat for security. Our key is
available at

You can verify each package with the following command:

rpm --checksig -v

If you only wish to verify that each package has not been corrupted or
tampered with, examine only the md5sum with the following command:


7. References:

8. Contact:

The Red Hat security contact is . More contact
details at

Copyright 2003 Red Hat, Inc.

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