alert http1 $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE FIN12 Related WEIRDLOOP/Cobalt Strike Beacon Activity (GET)"; flow:established,to_server; http.request_line; content:"GET|20|/image-directory/bn.ico|20|HTTP/1.1"; fast_pattern; http.header_names; content:"|0d 0a|Connection|0d 0a|Accept-Language|0d 0a|User-Agent|0d 0a|Host|0d 0a|Cache-Control|0d 0a 0d 0a|"; http.accept_lang; bsize:20; content:"en-GB|3b|q=0.9,|20|*|3b|q=0.7"; reference:md5,fd81452a3a8f9460ffac8aff6e20431a; reference:url,www.mandiant.com/resources/fin12-ransomware-intrusion-actor-pursuing-healthcare-targets; classtype:trojan-activity; sid:2034186; rev:3; metadata:attack_target Client_Endpoint, created_at 2021_10_13, deployment Perimeter, deployment SSLDecrypt, malware_family CobaltStrike, malware_family Fin12, confidence Medium, signature_severity Major, tag c2, updated_at 2024_04_04, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;)