alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE BACKCONFIG CnC Downloader Activity"; flow:established,to_server; http.uri; bsize:21; content:"/request/httpsrequest"; fast_pattern; http.host; pcre:"/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/"; http.header_names; to_lowercase; content:!"|0d 0a|referer|0d 0a|"; reference:url,unit42.paloaltonetworks.com/updated-backconfig-malware-targeting-government-and-military-organizations; classtype:trojan-activity; sid:2030165; rev:4; metadata:attack_target Client_Endpoint, created_at 2020_05_13, deployment Perimeter, malware_family APT_HANGOVER, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_05_04;)