ET WEB_SPECIFIC_APPS xml-crypto / Node.js SAML Authentication Bypass Forged DigestValue Comment (CVE-2025-29775)

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET WEB_SPECIFIC_APPS xml-crypto / Node.js SAML Authentication Bypass Forged DigestValue Comment (CVE-2025-29775)";
    flow:established,to_server;
    http.method;
    content:"POST";
    http.request_body;
    content:"SAMLResponse|3d|"; fast_pattern;
    base64_decode:offset 0, relative;
    base64_data;
    content:"|3c|saml2p|3a|Response";
    content:"|3c|DigestValue|3e 3c 21 2d 2d|";
    pcre:"/^[A-Za-z0-9\x2b\x2f]+\x3d*\x2d\x2d\x3e[A-Za-z0-9\x2b\x2f]+\x3d*\x3c\x2fds\x3aDigestValue\x3e/R";
    reference:url,workos.com/blog/samlstorm;
    reference:cve,2025-29775;
    classtype:web-application-attack;
    sid:2060960; rev:2;
    metadata:affected_product Node_js, attack_target Server, tls_state TLSDecrypt, created_at 2025_03_19, cve CVE_2025_29775, deployment Perimeter, deployment Internal, deployment SSLDecrypt, confidence Medium, signature_severity Major, tag Exploit, updated_at 2025_03_25, reviewed_at 2025_08_26, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application;
    target:dest_ip;
)