alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE StealC_V2 CnC Activity (POST)"; flow:established,to_server; urilen:<24; http.method; content:"POST"; http.uri; pcre:"/^\x2f(?:[a-z0-9]{14,19})\x2ephp$/"; http.header_names; bsize:67; content:"|0d 0a|content-type|0d 0a|host|0d 0a|content-length|0d 0a|connection|0d 0a|cache-control|0d 0a 0d 0a|"; nocase; fast_pattern; http.content_type; content:"application/json"; http.content_len; bsize:3; pcre:"/^\d{3}$/"; http.connection; content:"Keep-Alive"; http.header; content:"Cache|2d|Control|3a20|no|2d|cache"; http.request_body; pcre:"/^(?:[a-zA-Z0-9\x2b\x2f\x3d]){100}/"; classtype:command-and-control; sid:2066280; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, tls_state plaintext, created_at 2025_12_11, deployment Perimeter, deployment SSLDecrypt, malware_family Stealc, performance_impact Moderate, confidence High, signature_severity Major, tag c2, updated_at 2025_12_11, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol; target:src_ip;)