Secunia Security Advisory - siouxsie has reported a vulnerability in Snort, which potentially can be exploited by malicious people to bypass certain security restrictions.
688bf22739774bfa0a89ab63a958ca03f0fcb16989cc0538805fde9848594810
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
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