alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE MSIL/Agent.PYO Retrieving Update"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/data_updater.dat"; fast_pattern; pcre:"/\/data_updater\.dat$/"; http.header; pcre:"/^Host\x3a[^\r\n]+\r\n(?:\r\n)?$/"; http.header_names; content:!"User-Agent|0d 0a|"; content:!"Accept"; content:!"Referer|0d 0a|"; reference:url,welivesecurity.com/2015/01/29/msilagent-pyo-have-botnet-will-travel/; classtype:trojan-activity; sid:2020333; rev:4; metadata:created_at 2015_01_30, malware_family MSIL_Agent_PYO, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_09_29;)