alert tcp $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE NetWire Variant - Server Directory Listing Request"; flow:established,to_client; flowbits:isset,ET.NetWire; content:"|01|"; depth:1; content:"|00 00 00 06 43 3A|"; distance:1; within:6; reference:url,researchcenter.paloaltonetworks.com/2014/08/new-release-decrypting-netwire-c2-traffic; reference:url,www.circl.lu/pub/tr-23; classtype:trojan-activity; sid:2021979; rev:2; metadata:created_at 2015_10_20, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_07_26;)