ET EXPLOIT [CORELIGHT] - CVE-2025-27218 Sitecore unsafe deserialization attempt

alert http any any -> [$HOME_NET,$HTTP_SERVERS] any (
    msg:"ET EXPLOIT [CORELIGHT] - CVE-2025-27218 Sitecore unsafe deserialization attempt";
    flow:established,to_server;
    http.header;
    content:"thumbnailsaccesstoken|3a 20|"; nocase;
    content:"AQAAAAAAAAAEAQAAAClTeXN0ZW0uU2VjdXJpdHkuUHJpbmNpcGF"; fast_pattern; distance:0;
    reference:url,slcyber.io/blog/sitecore-unsafe-deserialization-again-cve-2025-27218/;
    reference:cve,2025-27218;
    classtype:attempted-admin;
    sid:2060777; rev:2;
    metadata:attack_target Server, created_at 2025_03_10, cve CVE_2025_27218, deployment Perimeter, deployment Internal, confidence High, signature_severity Major, tag Exploit, updated_at 2025_03_28, reviewed_at 2025_08_06, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application;
    target:dest_ip;
)