alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Ddex Loader Check-in"; flow:established,to_server; http.method; content:"GET"; http.uri; content:".php?t="; content:"&o="; content:"&i="; content:"&task_id="; http.header_names; content:!"Referer|0d 0a|"; reference:url,securelist.com/files/2014/07/Kaspersky_Lab_crouching_yeti_appendixes_eng_final.pdf; classtype:trojan-activity; sid:2018895; rev:3; metadata:created_at 2014_08_05, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_05_01;)