[prev in list] [next in list] [prev in thread] [next in thread] 

List:       secunia-sec-adv
Subject:    [SA18959] Snort frag3 Preprocessor Packet Reassembly Vulnerability
From:       Secunia Security Advisories <sec-adv () secunia ! com>
Date:       2006-02-27 15:32:04
Message-ID: 20060227153204.25865.qmail () secunia ! com
[Download RAW message or body]


TITLE:
Snort frag3 Preprocessor Packet Reassembly Vulnerability

SECUNIA ADVISORY ID:
SA18959

VERIFY ADVISORY:
http://secunia.com/advisories/18959/

CRITICAL:
Moderately critical

IMPACT:
Security Bypass

WHERE:
From remote

SOFTWARE:
Snort 2.4.x
http://secunia.com/product/5691/

DESCRIPTION:
siouxsie has reported a vulnerability in Snort, which potentially can
be exploited by malicious people to bypass certain security
restrictions.

The vulnerability is caused due to an error in the frag3 preprocessor
which causes snort to skip "ip_option_length" bytes from the end of
the IP options when reassembling a packet. This can potentially be
exploited to bypass signature detection via certain specially-crafted
fragmented packets.

The vulnerability has been reported in version 2.4.3. Other versions
may also be affected.

SOLUTION:
Filter potentially malicious fragmented IP packets with a firewall.

PROVIDED AND/OR DISCOVERED BY:
siouxsie

----------------------------------------------------------------------

About:
This Advisory was delivered by Secunia as a free service to help
everybody keeping their systems up to date against the latest
vulnerabilities.

Subscribe:
http://secunia.com/secunia_security_advisories/

Definitions: (Criticality, Where etc.)
http://secunia.com/about_secunia_advisories/


Please Note:
Secunia recommends that you verify all advisories you receive by
clicking the link.
Secunia NEVER sends attached files with advisories.
Secunia does not advise people to install third party patches, only
use those supplied by the vendor.

----------------------------------------------------------------------

Unsubscribe: Secunia Security Advisories
http://secunia.com/sec_adv_unsubscribe/?email=secunia-sec-adv%40progressive-comp.com

----------------------------------------------------------------------
[prev in list] [next in list] [prev in thread] [next in thread]