Vulnerability Note VU#240790

tcpdump contains buffer overflow vulnerability in ISAKMP "Delete Payload" handling

Original Release date: 27 Aug 2004 | Last revised: 27 Aug 2004


A vulnerability in tcpdump could allow a remote attacker to cause a denial of service on an affected system.


The tcpdump tool allows for the inspection of network packets and contains decoders for many standard protocols, including the Internet Security Association and Key Management Protocol (ISAKMP). The ISAKMP standard specifies:

    The Delete Payload contains a protocol-specific security association identifier that the sender has removed from its security association database and is, therefore, no longer valid. [...] It is possible to send multiple Security Parameter Index(es) (SPIs) in a Delete payload [...]

To this end, the format of the "Delete Payload" contains a "# of SPIs" field, specified as two octets. A buffer overflow flaw exists in the way that tcpdump's ISAKMP decoder handles malformed ISAKMP packets specifying an overly large number of SPIs for deletion. Such malformed packets could cause tcpdump to read out of bounds and crash. This condition is only exploitable if tcpdump is invoked with the verbose display option, '-v'.


A remote attacker could cause tcpdump to crash.


Apply a patch from the vendor

Patches have been released to address this issue. Please see the Systems Affected section of this document for more details.

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
DebianAffected-26 Aug 2004
Fedora ProjectAffected-26 Aug 2004
Gentoo LinuxAffected-26 Aug 2004
MandrakeSoftAffected-26 Aug 2004
OpenPKGAffected-26 Aug 2004
Red Hat Inc.Affected-26 Aug 2004
SGIAffected-26 Aug 2004
SlackwareAffected-26 Aug 2004
SuSE Inc.Affected-26 Aug 2004
Trustix Secure LinuxAffected-26 Aug 2004
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A



This vulnerability was discovered by Rapid7 using their Striker test suite.

This document was written by Chad R Dougherty based on information published in Rapid7 Advisory R7-0017.

Other Information

  • CVE IDs: CAN-2004-0183
  • Date Public: 30 Mar 2004
  • Date First Published: 27 Aug 2004
  • Date Last Updated: 27 Aug 2004
  • Severity Metric: 1.69
  • Document Revision: 14


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