Rule:  
 
--
Sid:
627

--
Summary:
This event is generated when the Cybercop vulnerability scanner is used against a host.

--
Impact:
Cybercop can be used to identify vulnerabilities on host systems.

--
Detailed Information:
This particular packet is a part of Cybercop's OS identification. Specially crafted packets are able to elicit different responses from different operating systems.  This packet is likely to be part of a full Cybercop scan rather than an isolated event. Having SYN, FIN, URG and reserve bits 1 and 2 set at the same time is abnormal.

--
Affected Systems:
All

--
Attack Scenarios:
Cybercop can be used by attackers to determine vulnerabilities present on a host or network of hosts that could be used as attack vectors.

--
Ease of Attack:
Simple

--
False Positives:
This tool can be used legitimately by system and network administrators. Other vulnerability scanners may display the same behavior.

--
False Negatives:
None known.

--
Corrective Action:
TCP packets with SYN, FIN, URG and reserved bits 1 and 2 set at the same time are abnormal, use a packet filtering firewall to block them.

--
Contributors:
Original Rule Writer Unknown
Sourcefire Vulnerability Research Team
Nigel Houghton <nigel.houghton@sourcefire.com>
Snort documentation contributed by Steven Alexander<alexander.s@mccd.edu>

-- 
Additional References:

--
