GEN:SID 1:247
Message DDOS mstream client to handler
Summary This event is generated when an mstream DDoS client communicates with a handler.
Impact Severe.  If the listed source IP is in your network, it may be an mstream client.  If the listed destination IP is in your network, it may be an mstream handler.
Detailed Information The mstream DDoS uses a tiered structure of compromised hosts to coordinate and participate in a distributed denial of service attack. At the highest level, clients communicate with handlers to inform them to launch attacks.  A client may communicate with a handler using a TCP packet to destination port 12754 with a string of ">" in the payload.
Affected Systems Any mstream compromised host.
Attack Scenarios After a host becomes an mstream client, it will attempt to communicate with handlers.
Ease of Attack Simple. mstream code is freely available.
Corrective Action Perform proper forensic analysis on the suspected compromised host to discover the means of compromise.

Rebuild a confirmed compromised host.

Use a packet-filtering firewall to block inappropriate traffic to the network to prevent hosts from being compromised.
Additional References CVE:
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2000-0138
Rule References cve: 2000-0138