ET MALWARE Tinba Checkin 2

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE Tinba Checkin 2";
    flow:established,to_server;
    urilen:>1;
    flowbits:set,ET.Tinba.Checkin;
    content:"|0d 0a 0d 0a|";
    content:!"|00 00 00 00|"; within:4;
    content:!"|FF FF FF FF|"; within:4;
    byte_extract:2,2,Tinba.Pivot,relative;
    byte_test:2,=,Tinba.Pivot,2,relative;
    byte_test:2,!=,Tinba.Pivot,5,relative;
    http.method;
    content:"POST";
    http.uri;
    content:"/"; endswith;
    http.content_len;
    byte_test:0,>,99,0,string,dec;
    http.protocol;
    content:"HTTP/1.0";
    http.header_names;
    content:"|0d 0a|Host|0d 0a|Content-Length|0d 0a 0d 0a|"; fast_pattern;
    content:!"User-Agent";
    content:!"Accept";
    reference:md5,7af6d8de2759b8cc534ffd72fdd8a654;
    classtype:command-and-control;
    sid:2020418; rev:7;
    metadata:created_at 2015_02_12, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_09_14;
)