ET MALWARE FOX-SRT ShimRat check-in (Yuok)

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;
)