ET EXPLOIT Cisco IOS XE Web Server Implant Check (CVE-2023-20198) (Inbound) M1

alert http $EXTERNAL_NET any -> [$HOME_NET,$HTTP_SERVERS] any (
    msg:"ET EXPLOIT Cisco IOS XE Web Server Implant Check (CVE-2023-20198) (Inbound) M1";
    flow:established,to_server;
    urilen:38;
    http.method;
    content:"POST";
    http.uri;
    content:"/webui/logoutconfirm.html?logon_hash=1"; fast_pattern;
    threshold:type limit,seconds 300,count 1,track by_src;
    reference:url,blog.talosintelligence.com/active-exploitation-of-cisco-ios-xe-software/;
    reference:cve,2023-20198;
    classtype:trojan-activity;
    sid:2048584; rev:2;
    metadata:affected_product iOS, attack_target Web_Server, created_at 2023_10_17, cve CVE_2023_20198, deployment Perimeter, deployment Internet, deployment SSLDecrypt, confidence High, signature_severity Major, tag CISA_KEV, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_10_30, reviewed_at 2024_01_26;
)