alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE FOX-SRT ShimRat check-in (Yuok)"; flow:established,to_server; threshold:type limit, track by_src, count 1, seconds 600; http.method; content:"POST"; http.uri; content:".php"; endswith; http.request_body; content:"Youk$$"; fast_pattern; content:"Youk"; endswith; pcre:"/^(?:php)?Yuok\$\$\d\d/"; http.header_names; content:"|0d 0a|User-Agent|0d 0a|"; depth:14; content:!"Content-Type|0d 0a|"; content:!"Referer|0d 0a|"; content:!"Cookie|0d 0a|"; reference:url,blog.fox-it.com/2016/06/15/mofang-a-politically-motivated-information-stealing-adversary/; classtype:trojan-activity; sid:2022902; rev:6; metadata:created_at 2016_06_15, signature_severity Major, updated_at 2022_03_24;)