ET WEB_SPECIFIC_APPS SmarterTools SmarterMail ConnectToHub Unauthenticated Remote Code Execution (CVE-2026-24423)

alert http $EXTERNAL_NET any -> $HOME_NET any (
    msg:"ET WEB_SPECIFIC_APPS SmarterTools SmarterMail ConnectToHub Unauthenticated Remote Code Execution (CVE-2026-24423)";
    flow:established,to_client;
    http.response_body;
    content:"|22|ClusterID|22 3a|";
    content:"|22|isStandby|22 3a|";
    content:"|22|false|22|"; nocase; within:8;
    content:"|22|SystemMount|22 3a|";
    content:"|22|CommandMount|22 3a|"; fast_pattern;
    reference:url,xz.aliyun.com/news/91523;
    reference:cve,2026-24423;
    classtype:web-application-attack;
    sid:2067266; rev:1;
    metadata:affected_product SmarterTools_SmarterMail, attack_target Server, tls_state TLSDecrypt, created_at 2026_02_03, cve CVE_2026_24423, deployment Perimeter, deployment Internal, deployment SSLDecrypt, confidence High, signature_severity Major, tag Exploit, updated_at 2026_02_03, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application;
    target:dest_ip;
)