ET MALWARE FakeAV Check-in purporting to be MSIE with invalid terse HTTP headers

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE FakeAV Check-in purporting to be MSIE with invalid terse HTTP headers";
    flow:established,to_server;
    http.user_agent;
    content:"Mozilla/4.0|20|(compatible|3b 20|MSIE|20|"; depth:30;
    http.request_body;
    content:"data="; depth:5; fast_pattern;
    http.accept;
    content:"*/*"; depth:3; endswith;
    http.content_type;
    content:"application/x-www-form-urlencoded"; depth:33; endswith;
    http.header_names;
    content:"|0d 0a|Accept|0d 0a|Content-Type|0d 0a|Host|0d 0a|"; depth:30;
    content:"User-Agent|0d 0a|"; distance:0;
    content:"Content-Length|0d 0a|"; distance:0;
    classtype:trojan-activity;
    sid:2012627; rev:5;
    metadata:created_at 2011_04_04, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_09_15;
)