alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE TA404 Comebacker Related Activity (POST)"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"/upload.asp"; endswith; fast_pattern; http.header_names; strip_pseudo_headers; to_lowercase; content:"|0d 0a|content-type|0d 0a|connection|0d 0a|"; startswith; content:!"|0d 0a|referer|0d 0a|"; http.cookie; content:"ASPSESSIONID"; content:!"="; within:8; reference:md5,d8a8cc25bf5ef5b96ff7a64f663cbd29; classtype:trojan-activity; sid:2049276; rev:2; metadata:attack_target Client_Endpoint, created_at 2023_11_21, deployment Perimeter, performance_impact Moderate, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_27; target:src_ip;)