Ethereal fails to properly handle malformed SMB packets

2004-09-07T00:00:00
ID VU:518782
Type cert
Reporter CERT
Modified 2004-10-08T00:00:00

Description

Overview

Ethereal contains a vulnerability in the way it processes Server Message Block (SMB) packets.

Description

The Server Message Block (SMB) protocol is used for sharing files, printers, and other resources between computers. SMB is used in Microsoft Windows to provide file and print services. Ethereal includes the ability to decode packets containing SMB data. There is a vulnerability in the way the SMB dissector decodes SMB packets containing a policy name without a handle. If SID snooping is enabled, this could trigger a null pointer dereference and a remote, unauthenticated attacker could cause Ethereal to crash or potentially execute code of the attacker's choice.


Impact

A remote, unauthenticated attacker could cause Ethereal to crash or potentially execute code of the attacker's choice.


Solution

Upgrade

Upgrade to version 0.10.5 or later.

Note: Ethereal is considered BETA software at this time.


Disable SID Snooping

1) Select Edit --> Preferences
2) Expand the Protocols section
3) Select SMB
4) Disable the checkbox for "Snoop SID to Name mappings"

However, it is strongly encouraged to upgrade to version 0.10.5 or later.


Systems Affected

Vendor| Status| Date Notified| Date Updated
---|---|---|---
Ethereal| | -| 01 Sep 2004
If you are a vendor and your product is affected, let us know.

CVSS Metrics

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

References

  • <http://www.ethereal.com/appnotes/enpa-sa-00015.html>
  • <http://xforce.iss.net/xforce/xfdb/16631>
  • <http://secunia.com/advisories/12024/>
  • <http://www.securityfocus.com/bid/10672>
  • <http://www.securitytracker.com/alerts/2004/Jul/1010655.html>
  • <http://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=127381>
  • <http://www.redhat.com/support/errata/RHSA-2004-378.html>
  • <http://www.redhat.com/archives/fedora-announce-list/2004-July/msg00013.html>
  • <http://www.redhat.com/archives/fedora-announce-list/2004-July/msg00014.html>
  • <http://www.gentoo.org/security/en/glsa/glsa-200407-08.xml>
  • <http://www.mandrakesecure.net/en/advisories/advisory.php?name=MDKSA-2004:067>

Credit

This vulnerability was reported by the maintainers of Ethereal.

This document was written by Damon Morda.

Other Information

  • CVE IDs: CAN-2004-0634
  • Date Public: 06 Jul 2004
  • Date First Published: 07 Sep 2004
  • Date Last Updated: 08 Oct 2004
  • Severity Metric: 8.09
  • Document Revision: 14