ET POLICY Socks5 Proxy to Onion (set)

alert tcp $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET POLICY Socks5 Proxy to Onion (set)";
    flow:established,to_server;
    flowbits:set,ET.Socks5.OnionReq;
    content:"|05 01 00 03|"; depth:4;
    content:".onion|00 50|"; distance:0; fast_pattern;
    reference:url,www.intezer.com/blog-seizing-15-active-ransomware-campaigns-targeting-linux-file-storage-servers;
    classtype:policy-violation;
    sid:2027703; rev:1;
    metadata:attack_target Client_Endpoint, created_at 2019_07_11, deployment Perimeter, performance_impact Moderate, confidence High, signature_severity Major, updated_at 2019_07_26;
)