alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Suspected Gamaredon Downloader Activity"; flow:established,to_server; http.method; content:"GET"; http.uri.raw; content:"//autoindex.php"; endswith; fast_pattern; http.host; content:".ddns.net"; endswith; http.header_names; content:!"Referer"; reference:url,blog.yoroi.company/research/cyberwarfare-a-deep-dive-into-the-latest-gamaredon-espionage-campaign/; classtype:trojan-activity; sid:2029500; rev:2; metadata:attack_target Client_Endpoint, created_at 2020_02_19, deployment Perimeter, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_02_19;)