alert http $HOME_NET any -> $EXTERNAL_NET [7080,8080,443,80,4143,995,21,50000,20,8090,8443,990,22] (msg:"ET MALWARE Win32/Emotet CnC Activity (POST) M8"; flow:established,to_server; http.method; content:"POST"; http.uri; content:!"."; content:!"&"; content:!"-"; content:!"?"; http.user_agent; content:"Mozilla/4.0 (compatible|3b 20|MSIE 7.0|3b 20|Windows NT 6."; startswith; http.request_body; content:"Content-Disposition|3a 20|form-data|3b 20|name=|22|"; pcre:"/^[A-Za-z]{5,20}\x22\x3b\x20filename=\x22[A-Za-z]{5,20}\x22/R"; content:"|0d 0a|Content-Type|3a 20|application/octet-stream|0d 0a 0d 0a|"; within:44; content:"|2d 2d 00 00 00 00 00 00 00 00 00 00|"; distance:0; fast_pattern; content:"|00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|"; endswith; http.content_type; content:"multipart/form-data|3b 20|boundary=---------------------------"; startswith; pcre:"/^\d{15}$/R"; http.content_len; byte_test:0,<,5000,0,string,dec; byte_test:0,>,4000,0,string,dec; http.start; pcre:"/^POST\s(?P<urivar>\/(?:[A-Z0-9a-z]{2,25}\/){1,10})\sHTTP\/1\.1\r\nReferer\x3a\x20http:\/\/(?:\d{1,3}\.){3}\d{1,3}(?:\x3a[0-9]{2,5})?(?P=urivar)\r\n/"; http.header_names; content:"|0d 0a|Referer|0d 0a|Content-Type|0d 0a|User-Agent|0d 0a|Host|0d 0a|Content-Length|0d 0a|"; depth:59; classtype:command-and-control; sid:2029380; rev:6; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2020_02_05, deployment Perimeter, malware_family Emotet, confidence High, signature_severity Major, tag Emotet, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_05_22;)