alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET DELETED CozyDuke APT HTTP Checkin"; flow:established,to_server; content:"GET"; http_method; content:".php?"; http_uri; fast_pattern:only; content:!"Accept"; http_header; content:!"Referer|3a|"; http_header; content:"User-Agent|3a 20|Mozilla/"; depth:20; http_header; pcre:"/\.php\?$/U"; reference:url,securelist.com/blog/69731/the-cozyduke-apt/; reference:md5,98a6484533fa12a9ba6b1bd9df1899dc; classtype:targeted-activity; sid:2020962; rev:4; metadata:created_at 2015_04_22, signature_severity Unknown, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_07_26;)