ET MALWARE LNK/Unknown Downloader CnC Checkin (POST)

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE LNK/Unknown Downloader CnC Checkin (POST)";
    flow:established,to_server;
    urilen:1;
    http.method;
    content:"POST";
    http.host;
    pcre:"/^(?:[0-9]{1,3}\.){3}[0-9]{1,3}$/";
    http.user_agent;
    content:"Mozilla|2f|4|2e|0|20 28|compatible|3b 20|Synapse|29|"; bsize:33;
    http.header;
    content:"Keep-Alive: 300|0d 0a|";
    http.connection;
    content:"keep-alive"; bsize:10;
    http.content_type;
    content:"application|2f|x|2d|www|2d|form|2d|urlencoded";
    http.request_body;
    content:"id="; startswith;
    content:"&data=";
    content:"&act=100";
    isdataat:!2,relative; fast_pattern;
    reference:md5,0185e0fc2f505312001e1a65e6783908;
    reference:url,twitter.com/Gi7w0rm/status/1693432581583184029;
    classtype:trojan-activity;
    sid:2047717; rev:1;
    metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2023_08_23, deployment Perimeter, deployment SSLDecrypt, confidence Medium, signature_severity Critical, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_08_23, reviewed_at 2023_08_23;
)