alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Bitter RAT HTTP CnC Beacon M2"; flow:established,to_server; threshold:type both, count 5, seconds 120, track by_src; http.method; content:"GET"; http.uri; content:".php?TIe="; fast_pattern; pcre:"/^[a-zA-Z0-9\x21\x2a\x2f\x2e\x3b\x3a\x5b\x5d\x7b\x7d]+$/R"; http.header_names; content:!"User-Agent|0d 0a|"; content:!"Accept"; content:!"Referer"; reference:url,community.rsa.com/community/products/netwitness/blog/2018/01/10/malspam-delivers-bitter-rat-07-01-2018; reference:md5,cc58dd8592555ff6275196e62af3242e; reference:md5,8d42c01180be7588a2a68ad96dd0cf85; classtype:command-and-control; sid:2025198; rev:4; metadata:attack_target Client_Endpoint, created_at 2018_01_11, deployment Perimeter, confidence High, signature_severity Major, tag c2, updated_at 2020_08_27, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;)