alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE W32/Depyot.Downloader CnC Beacon"; flow:established,to_server; http.uri; content:"/pdf.php?id="; fast_pattern; http.user_agent; content:"Mozilla/4.0 (compatible)"; bsize:24; reference:url,www.fireeye.com/blog/technical/targeted-attack/2013/03/internet-explorer-8-exploit-found-in-watering-hole-campaign-targeting-chinese-dissidents.html; reference:url,www.microsoft.com/security/portal/threat/encyclopedia/entry.aspx?Name=TrojanDownloader%3AWin32%2FDepyot.A&ThreatID=-2147288740; classtype:command-and-control; sid:2016638; rev:3; metadata:attack_target Client_Endpoint, created_at 2013_03_22, deployment Perimeter, signature_severity Major, tag c2, updated_at 2020_04_23, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;)