alert http1 $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE [ANY.RUN] DarkGate Check-In HTTP Header (POST)"; flow:established,to_server; flowbits:set,ET.DarkGate.1; urilen:1; http.method; content:"POST"; http.connection; bsize:10; content:"keep-alive"; http.content_type; bsize:24; content:"Application/octet-stream"; http.header; content:"Keep-Alive|3a 20|300|0d 0a|"; content:"Content-Length|3a 20|"; byte_test:0,>,40,0,relative,string,dec; byte_test:0,<,750,0,relative,string,dec; http.header_names; bsize:76; content:"|0d 0a|Host|0d 0a|Keep-Alive|0d 0a|Connection|0d 0a|User-Agent|0d 0a|Content-Type|0d 0a|Content-Length|0d 0a 0d 0a|"; http.user_agent; bsize:33; content:"Mozilla|2f|4|2e|0|20 28|compatible|3b 20|Synapse|29|"; fast_pattern; threshold:type limit,seconds 300,count 1,track by_src; reference:md5,4d26c05426247f7a4f784967c7b0faa2; reference:url,app.any.run/tasks/fb92bcf3-3413-4bca-807a-fb002ac48b18; reference:url,malware-traffic-analysis.net/2023/10/12/index.html; reference:url,community.emergingthreats.net/t/darkgate/1033; classtype:command-and-control; sid:2048558; rev:4; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2023_10_13, deployment Perimeter, malware_family DarkGate, confidence High, signature_severity Critical, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_03, reviewed_at 2023_10_13; target:src_ip;)