alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Possible Emissary External IP Lookup"; flow:established,to_server; urilen:12; http.method; content:"GET"; http.uri; content:"/index.shtml"; http.host; content:"b4secure.com"; endswith; fast_pattern; http.user_agent; content:"Mozilla/4.0 (compatible|3b 20|MSIE 6.0|3b 20|Win32)"; bsize:41; http.header_names; content:!"Accept"; content:!"Referer|0d 0a|"; reference:url,researchcenter.paloaltonetworks.com/2016/10/unit42-psa-conference-invite-used-lure-operation-lotus-blossom-actors/; classtype:external-ip-check; sid:2023470; rev:5; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2016_10_31, deployment Perimeter, malware_family Emissary, malware_family Lotus_Blossom, performance_impact Low, confidence High, signature_severity Informational, updated_at 2024_11_26, mitre_tactic_id TA0007, mitre_tactic_name Discovery, mitre_technique_id T1614, mitre_technique_name System_Location_Discovery;)