ET HUNTING Kubernetes Ingress NGINX Controller Annotation Injection

alert http $EXTERNAL_NET any -> $HOME_NET any (
    msg:"ET HUNTING Kubernetes Ingress NGINX Controller Annotation Injection";
    flow:established,to_server;
    http.method;
    content:"POST";
    http.content_type;
    content:"application/json";
    http.request_body;
    content:"|22|admission.k8s.io/v1|22 2c|";
    content:"|22|nginx.ingress.kubernetes.io/"; fast_pattern;
    pcre:"/^[a-z-]+\x22\x3a\s*?\x22[^\x22]*?(?:\x23|\x3b\x7d)/R";
    classtype:web-application-attack;
    sid:2061122; rev:1;
    metadata:affected_product Kubernetes, attack_target Server, tls_state TLSDecrypt, created_at 2025_03_27, deployment Perimeter, deployment Internal, deployment SSLDecrypt, confidence Medium, signature_severity Major, tag Exploit, updated_at 2025_03_27, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application;
    target:dest_ip;
)