alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE SideCopy Group Activity (GET)"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/css/css/b/l/i2.php"; bsize:19; fast_pattern; http.accept_enc; content:"gzip,|20|deflate"; bsize:13; http.header_names; content:!"Referer"; reference:url,twitter.com/ShadowChasing1/status/1422914152381616134; reference:url,twitter.com/c3rb3ru5d3d53c/status/1422982036365750275; reference:md5,896793b5a446fb3a648a7f290a2b38cd; reference:md5,8e07953b96ffa7ee7f5d0fa6fea71a6a; classtype:trojan-activity; sid:2033680; rev:1; metadata:attack_target Client_Endpoint, created_at 2021_08_05, deployment Perimeter, deployment SSLDecrypt, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_08_05;)