ET WEB_SPECIFIC_APPS Kaseya VSA Authenticated Reflected Cross-site Scripting (CVE-2021-30119) M1

alert http any any -> [$HOME_NET,$HTTP_SERVERS] any (
    msg:"ET WEB_SPECIFIC_APPS Kaseya VSA Authenticated Reflected Cross-site Scripting (CVE-2021-30119) M1";
    flow:established,to_server;
    http.request_line;
    content:"GET /HelpDeskTab/rcResults.asp?"; fast_pattern;
    content:"result|3d|";
    pcre:"/^[^&]*?(?:[\x20\x27\x22\x2f]on[a-z]+\x3d|(?:[^\x2f]s(?:cript[\x3a\x3e\x20\x2b\x2f]|tyle\x3d)|\x3ciframe[\x20\x2f]))/R";
    reference:url,csirt.divd.nl/cves/CVE-2021-30119/;
    reference:cve,2021-30119;
    classtype:web-application-attack;
    sid:2069325; rev:1;
    metadata:affected_product Kaseya_VSA, attack_target Server, tls_state TLSDecrypt, created_at 2026_05_18, cve CVE_2021_30119, deployment Perimeter, deployment Internal, deployment SSLDecrypt, confidence High, signature_severity Major, tag Exploit, updated_at 2026_05_18, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application;
    target:dest_ip;
)