ET MALWARE NOBELIUM (TA421) EnvyScout Fingerprint Checkin

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE NOBELIUM (TA421) EnvyScout Fingerprint Checkin";
    flow:established,to_server;
    http.method;
    content:"POST";
    http.content_type;
    content:"application/json"; bsize:16;
    http.request_body;
    content:"|7b 22|io|22 3a 22|"; startswith; fast_pattern;
    content:"|22 2c 22|tu|22 3a 22|"; distance:0;
    content:"|22 2c 22|sd|22 3a 22|"; distance:0;
    reference:url,www.microsoft.com/security/blog/2021/05/27/new-sophisticated-email-based-attack-from-nobelium/;
    reference:url,www.microsoft.com/security/blog/2021/05/28/breaking-down-nobeliums-latest-early-stage-toolset;
    classtype:command-and-control;
    sid:2033052; rev:3;
    metadata:affected_product Web_Browsers, attack_target Client_Endpoint, created_at 2021_05_28, deployment Perimeter, malware_family EnvyScout, confidence High, signature_severity Major, updated_at 2021_12_07;
)