ET WEB_SERVER Possible AntSword Webshell Commands Inbound

Query · suricata

flow:established,to_server;
http.method;
content:"POST";
http.request_body;
content:"Response.Write(|25|22"; within:50; nocase;
content:"eval(System.Text.Encoding.GetEncoding(|25|22"; nocase; distance:0;
content:"|25|22).GetString(System.Convert.FromBase64String(|25|22"; nocase; distance:0;
content:")|25|3BResponse.End()|25|3B&"; nocase; distance:0; fast_pattern;
Raw source ET WEB_SERVER Possible AntSword Webshell Commands Inbound · Suricata
Esc
Published by Emerging Threats Open ↗, licensed under BSD 3-Clause ↗. Line breaks added for readability; the rule is otherwise unchanged. 
alert http $EXTERNAL_NET any -> any any (
    msg:"ET WEB_SERVER Possible AntSword Webshell Commands Inbound";
    flow:established,to_server;
    http.method;
    content:"POST";
    http.request_body;
    content:"Response.Write(|25|22"; within:50; nocase;
    content:"eval(System.Text.Encoding.GetEncoding(|25|22"; nocase; distance:0;
    content:"|25|22).GetString(System.Convert.FromBase64String(|25|22"; nocase; distance:0;
    content:")|25|3BResponse.End()|25|3B&"; nocase; distance:0; fast_pattern;
    reference:url,github.com/AntSwordProject/antSword;
    classtype:web-application-attack;
    sid:2030037; rev:2;
    metadata:affected_product Web_Server_Applications, attack_target Web_Server, created_at 2020_04_28, deployment Perimeter, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_04_28;
)

Detection rules belong to the projects that publish them and remain under their own licenses. This site indexes and links to them; it claims no rights in them.