a method for detecting malicious programs within a computer network includes monitoring at least one first packet of data communicated over the network , analyzing the at least one first packet of data to detect the presence of a malicious program , generating a signature of the at least one first packet of data when a malicious program is detected , monitoring at least one second packet of data communicated over the network and detecting evidence of the malicious program in the at least one second packet of data utilizing the generated signature .