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.
- 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
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:
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.
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