ET MALWARE MSIL/Spy.Agent.CSS Exfil

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;
)