alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Suspected TA399/SideWinder Activity (GET)"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/files-"; offset:25; content:"/data?d="; distance:0; fast_pattern; http.header_names; content:!"User-Agent"; content:!"Referer"; content:!"Accept"; reference:md5,344b7370c6e61812eeb1cf1d737f27f3; reference:url,twitter.com/ShadowChasing1/status/1396809305194590211; classtype:trojan-activity; sid:2033032; rev:1; metadata:attack_target Client_Endpoint, created_at 2021_05_25, deployment Perimeter, malware_family Sidewinder, performance_impact Low, confidence Medium, signature_severity Major, tag TA399, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_05_25;)