alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET EXPLOIT_KIT Underminer EK Resource File Download M2"; flow:established,to_server; urilen:22; http.method; content:"GET"; http.uri; content:"/static/encrypt.min.js"; fast_pattern; http.header; content:"/"; content:".html|0d 0a|"; distance:26; within:7; http.referer; content:".html"; endswith; pcre:"/^[^\r\n]+(?![a-z]{26}|[0-9]{26})[a-z0-9]{26}\.html/i"; http.accept; content:"application/javascript, */*|3b|q=0.8"; classtype:exploit-kit; sid:2026423; rev:2; metadata:affected_product Web_Browsers, attack_target Client_Endpoint, created_at 2018_09_27, deployment Perimeter, confidence High, signature_severity Major, tag Underminer_EK, updated_at 2020_08_25;)