Rule:--Sid:653--Summary:This event is generated when suspicious shell code is detected innetwork traffic.--Impact:Denial of Service (DoS) possible execution of arbitrary code.--Detailed Information:This event is generated when suspicious shell code is detected. Manybuffer overflow attacks contain large numbers of NOOP instrucions to padout the request. Other attacks contain specific shell code sequencesdirected at certain applications or services.The shellcode in question may also use Unicode encoding.--Affected Systems:	Any software running on x86 architecture.--Attack Scenarios:An attacker may exploit a DCERPC service by sending shellcode in the RPCdata stream. Sending large amounts of data to the Microsoft Workstationservice can cause a buffer overflow condition in the logging functionthus presenting an attacker with the opportunity to issue a DoS attackor in some cases, to execute code of their choosing.--Ease of Attack:Simple. Many exploits exist.--False Positives:False positives may be generated by binary file transfers.--False Negatives:None known--Corrective Action:Make sure the target host has all current patches applied and has thelatest software versions installed.--Contributors:Sourcefire Vulnerability Research TeamBrian Caswell <bmc@sourcefire.com>Nigel Houghton <nigel.houghton@sourcefire.com>--Additional References:--