alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE FIN7 JSSLoader Variant Activity (GET)"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/?id="; startswith; fast_pattern; pcre:"/^[a-zA-z]{5,10}_[A-F0-9]{12}$/R"; http.header_names; content:!"Referer"; content:!"Accept"; reference:url,twitter.com/z0ul_/status/1399764964521488384; reference:md5,6a20636bed7deafe7317400bd18c7b9e; classtype:trojan-activity; sid:2033074; rev:1; metadata:attack_target Client_Endpoint, created_at 2021_06_02, deployment Perimeter, deployment SSLDecrypt, malware_family jssLoader, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_06_02;)