ET WEB_SPECIFIC_APPS Totolink setUpgradeUboot FileName Parameter Command Injection Attempt (CVE-2026-9531)

alert http any any -> $HOME_NET any (
    msg:"ET WEB_SPECIFIC_APPS Totolink setUpgradeUboot FileName Parameter Command Injection Attempt (CVE-2026-9531)";
    flow:established,to_server;
    http.method;
    content:"POST";
    http.uri; bsize:20;
    content:"/cgi-bin/cstecgi.cgi";
    http.request_body;
    content:"|22|topicurl|22|";
    content:"|22|setting/setUpgradeUboot|22|"; fast_pattern; within:30;
    content:"|22|FileName|22|";
    pcre:"/^(?:\x3a(?:\x20\x22|\x22))?[^\x2c\x7d$]*?(?:(?:\x3b|%3[Bb])|(?:\x0a|%0[Aa])|(?:\x60|%60)|(?:\x7c|%7[Cc])|(?:\x24|%24))+/R";
    reference:url,github.com/wudipjq/my_vuln/blob/main/totolink4/vuln_54/54.md;
    reference:cve,2026-9531;
    classtype:attempted-admin;
    sid:2070007; rev:1;
    metadata:affected_product TOTOLINK, attack_target Networking_Equipment, tls_state plaintext, created_at 2026_06_18, cve CVE_2026_9531, deployment Perimeter, deployment Internal, performance_impact Low, confidence High, signature_severity Major, tag Exploit, updated_at 2026_06_18, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application;
    target:dest_ip;
)