alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Foudre Checkin M1"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/de/?d=201"; depth:10; fast_pattern; content:"&t="; distance:0; http.host; pcre:"/^[a-f0-9]{8}\.(?:s(?:pac|it)e|net|top)$/"; http.header_names; content:!"Referer|0d 0a|"; reference:url,researchcenter.paloaltonetworks.com/2017/08/unit42-prince-persia-ride-lightning-infy-returns-foudre/; reference:url,twitter.com/ShadowChasing1/status/1339190981703266304; classtype:command-and-control; sid:2031411; rev:3; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2017_08_02, deployment Perimeter, performance_impact Moderate, confidence High, signature_severity Major, updated_at 2020_08_11;)