ET MALWARE BBSRAT POST request CnC

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE BBSRAT POST request CnC";
    flow:to_server,established;
    http.method;
    content:"POST";
    http.uri;
    content:"/bbs/"; depth:5; fast_pattern;
    content:"/forum.php?sid="; distance:0;
    pcre:"/^\/bbs\/(?P<counter>[a-f0-9]+)\/forum\.php\?sid=(?P=counter)$/i";
    http.user_agent;
    content:"Mozilla/4.0 (compatible|3b 20|Windows NT 5.1)"; startswith;
    http.cookie;
    pcre:"/[A-F0-9]{8}(?:-[A-F0-9]{4}){2}-[A-F0-9]{8}/";
    http.request_body;
    pcre:"/^[\x20-\x7e\r\n]{0,20}[^\x20-\x7e\r\n]/";
    reference:md5,8cd233d3f226cb1bf6bf15aca52e0e36;
    reference:url,researchcenter.paloaltonetworks.com/2015/12/bbsrat-attacks-targeting-russian-organizations-linked-to-roaming-tiger/;
    classtype:command-and-control;
    sid:2022311; rev:3;
    metadata:created_at 2015_12_24, signature_severity Major, updated_at 2020_06_16;
)