alert http $EXTERNAL_NET any -> $HTTP_SERVERS any (
msg:"ET EXPLOIT Apache Struts Possible OGNL Java WriteFile in client_body";
flow:to_server,established;
http.request_body;
content:"java.io.FileOutputStream"; nocase;
content:".write"; distance:0; nocase;
content:"sun.misc.BASE64Decoder"; nocase;
reference:url,struts.apache.org/development/2.x/docs/s2-013.html;
classtype:attempted-user;
sid:2016958; rev:4;
metadata:created_at 2013_06_01, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_04_24;
)