ET WEB_SPECIFIC_APPS Possible CrushFTP as2-to Anonymous User Rename Attempt (CVE-2023-43177)

alert http any any -> $HOME_NET any (
    msg:"ET WEB_SPECIFIC_APPS Possible CrushFTP as2-to Anonymous User Rename Attempt (CVE-2023-43177)";
    flow:established,to_server;
    http.method;
    content:"POST";
    http.uri;
    content:"/WebInterface/";
    http.header;
    content:"as2-to|3a 20|"; nocase;
    http.cookie;
    content:"CrushAuth|3d|"; startswith; fast_pattern;
    reference:cve,2023-43177;
    reference:url,convergetp.com/2023/11/16/crushftp-zero-day-cve-2023-43177-discovered/;
    classtype:attempted-user;
    sid:2049265; rev:1;
    metadata:attack_target FTP_Server, created_at 2023_11_20, cve CVE_2023_43177, deployment Perimeter, deployment Internet, performance_impact Low, confidence Low, signature_severity Major, updated_at 2023_11_20;
    target:dest_ip;
)