alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE MSIL/Black Hat Worm Checkin"; flow:established,to_server; content:"|7e 5c 77 6f 72 6d 73 5c 2e 42 6c 61 63 6b 20 48 61 74 20 57 6f 72 6d|"; startswith; content:"|62 6c 61 63 6b 20 68 61 74|"; distance:0; reference:md5,bfa67c998ebedf8ab17e2d8898d0067d; classtype:command-and-control; sid:2033716; rev:3; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_08_12, deployment Perimeter, malware_family MSIL_Black, performance_impact Low, confidence High, signature_severity Major, tag RAT, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_09_13;)