alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE VampireBot CnC Instruction Request (GET)"; flow:established,to_server; flowbits:set,ET.Vampire.Config; urilen:46; http.method; content:"GET"; http.uri; content:"/api/ping/"; fast_pattern; startswith; pcre:"/^(?:[a-z0-9]{8})\x2d(?:[a-z0-9]{4})\x2d(?:[a-z0-9]{4})\x2d(?:[a-z0-9]{4})\x2d(?:[a-z0-9]{12})$/R"; reference:md5,24670706f0a2cb915fcb683ba4cf55a6; classtype:command-and-control; sid:2064736; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, tls_state TLSDecrypt, created_at 2025_09_16, deployment Perimeter, deployment SSLDecrypt, malware_family VampireBot, confidence High, signature_severity Critical, tag c2, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2025_09_16, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol; target:src_ip;)