alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE MSIL/Spy.Agent.CSS Exfil"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"/stealer/"; startswith; fast_pattern; content:"?pwds="; distance:0; content:"&cards="; distance:0; content:"&user="; distance:0; content:"&comp="; distance:0; content:"&ip="; distance:0; http.user_agent; content:"OnionWClient"; startswith; http.header_names; content:!"|0d 0a|Referer|0d 0a|"; http.request_body; content:"Start|20|Date|3a 20|"; content:"Stub|20|Version|3a 20|"; distance:0; content:"Stub|20|Location|3a 20|"; distance:0; content:"|c2 bf 0a 0a|System|3a 0a 09|UserName|3a 20|"; distance:0; content:"|c2 be 0a 09|OSName|3a 20|"; distance:0; content:"Hardware|3a 0a 09|CPUName|3a 20|"; distance:0; reference:md5,c504c32724031c8f76df40b6b97c0338; classtype:trojan-activity; sid:2037812; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2022_07_22, deployment Perimeter, malware_family MSIL_Spy_Agent_CSS, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2022_07_22, reviewed_at 2025_01_06;)