ET WEB_SPECIFIC_APPS Possible VBulletin Unauthorized Admin Account Creation

alert http $EXTERNAL_NET any -> $HTTP_SERVERS any (
    msg:"ET WEB_SPECIFIC_APPS Possible VBulletin Unauthorized Admin Account Creation";
    flow:established,to_server;
    http.method;
    content:"POST";
    http.uri;
    content:"/upgrade.php"; nocase; fast_pattern;
    http.header;
    content:"Origin|3a|";
    http.request_body;
    content:"&customerid="; nocase;
    content:"&htmlsubmit=";
    content:"username"; nocase;
    content:"confirmpassword"; nocase;
    reference:url,blog.imperva.com/2013/10/threat-advisory-a-vbulletin-exploit-administrator-injection.html;
    classtype:web-application-attack;
    sid:2017575; rev:4;
    metadata:created_at 2013_10_10, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_09_21;
)