alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Possible TickGroup Casper CnC Activity"; flow:established,to_server; http.method; content:"POST"; http.user_agent; content:"Mozilla/4.0 (compatible|3b 20|MSIE 6.0|3b 20|Windows NT 5.1|3b 20|SV1|3b 20|.NET4.0C|3b 20|.NET4.0E)"; fast_pattern; http.header_names; strip_pseudo_headers; to_lowercase; content:"|0d 0a|accept|0d 0a|content-length|0d 0a|user-agent|0d 0a|"; startswith; reference:url,documents.trendmicro.com/assets/pdf/Operation-ENDTRADE-TICKs-Multistage-Backdoors-for-Attacking-Industries-and-Stealing-Classified-Data.pdf; classtype:command-and-control; sid:2029096; rev:4; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2019_12_04, deployment Perimeter, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_05_01;)