1. /
  2. Security Response/
  3. Snort TCP Packet Reassembly Integer Overflow Vulnerability

Snort TCP Packet Reassembly Integer Overflow Vulnerability

Risk

High

Date Discovered

April 15, 2003

Description

A vulnerability has been discovered in Snort. The problem occurs during the reassembly of TCP packets by the stream4 preprocesser. By sending specially crafted fragmented packets across a network monitored by Snort, it may be possible to trigger an integer overflow. As a result, a buffer overflow may occur, effectively allowing a remote attacker to corrupt heap memory. Successful exploitation of this issue could allow a remote attacker to execute arbitrary code on a target system. This issue effects Snort releases prior to Snort 2.0 RC1.

Technologies Affected

  • SmoothWall SmoothWall 2.0.0 Beta 4
  • Snort Project Snort 1.8.0
  • Snort Project Snort 1.8.1
  • Snort Project Snort 1.8.2
  • Snort Project Snort 1.8.3
  • Snort Project Snort 1.8.4
  • Snort Project Snort 1.8.4 beta1
  • Snort Project Snort 1.8.5
  • Snort Project Snort 1.8.6
  • Snort Project Snort 1.8.7
  • Snort Project Snort 1.9.0
  • Snort Project Snort 1.9.1

Recommendations

Run all software as a nonprivileged user with minimal access rights.

Configure Snort to run with the least privileges necessary whenever possible. This may limit the consequences of an attacker executing arbitrary code on a target system.

Implement multiple redundant layers of security.

The exploitability of this issue to execute arbitrary code may be hindered through the use of various memory protection schemes. Where permissible, implement the use of non-executable and randomly mapped memory pages.

Implement multiple redundant layers of security.

Where possible, implement multiple layers of network security. This may limit the consequences of a network sensor or firewall from being made unavailable.
Conectiva Linux has released a security advisory (CLSA-2003:671) to address this issue. Fixes are available below. Users are advised to upgrade as soon as possible. Guardian Digital Security has released a security advisory for EnGarde Secure Linux (ESA-20030430-013). The referenced advisory contains information pertaining to obtaining and applying fixes that address this issue. Users are advised to upgrade as soon as possible. While NetBSD does not include Snort by default, Snort is available through pkgsrc. NetBSD users who have installed Snort packages should use pkgsrc/security/audit-packages to apply upgrades. It is recommended that all Gentoo Linux users who are running net-analyzer/snort upgrade to snort-2.0.0 as follows: emerge sync emerge snort emerge clean Mandrake has released a security advisory (MDKSA-2003:052) which contains fixes that address this issue. Users are advised to upgrade as soon as possible. Debian has released a security advisory (DSA 297-1) containing fixes which address this issue. Users are advised to upgrade as soon as possible. This issue is addressed in Snort 2.0. Users are advised to upgrade. Fixes are available:

Credits

Discovery of this issue is credited to Bruce Leidl, Juan Pablo Martinez Kuhn and Alejandro David Weil from Core Security Technologies.
Copyright © Symantec Corporation.
Permission to redistribute this alert electronically is granted as long as it is not edited in any way unless authorized by Symantec Security Response. Reprinting the whole or part of this alert in any medium other than electronically requires permission from secure@symantec.com.

Disclaimer
The information in the advisory is believed to be accurate at the time of publishing based on currently available information. Use of the information constitutes acceptance for use in an AS IS condition. There are no warranties with regard to this information. Neither the author nor the publisher accepts any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information.
Symantec, Symantec products, Symantec Security Response, and secure@symantec.com are registered trademarks of Symantec Corp. and/or affiliated companies in the United States and other countries. All other registered and unregistered trademarks represented in this document are the sole property of their respective companies/owners.

Threat Intelligence

Subscribe
Follow the Threat Intelligence Twitter feed
STAR Antimalware Protection Technologies
Internet Security Threat Report
Symantec DeepSight Screensaver