alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE DonotGroup Pult Downloader Activity M3"; flow:established,to_server; urilen:8<>30; http.method; content:"POST"; http.uri; content:!".php"; pcre:"/^\/[A-Z][a-z]+\/[a-z]+$/"; http.content_type; content:"application/x-www-form-urlencoded"; bsize:33; http.request_body; content:"meta="; startswith; fast_pattern; content:!"W3si"; within:4; pcre:"/^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=|[A-Za-z0-9+/]{4})$/R"; http.content_len; byte_test:0,<,3000,0,string,dec; byte_test:0,>,100,0,string,dec; http.user_agent; content:!"Linux|3b|"; content:!"iPhone|3b|"; http.header_names; content:!"Referer"; content:"|0d 0a|Content-Type|0d 0a|"; startswith; nocase; content:"User-Agent|0d 0a|Host|0d 0a|Content-Length|0d 0a|Cache-Control|0d 0a 0d 0a|"; within:51; bsize:67; reference:md5,a8ed32cbb01f830d247ea265358c395d; classtype:trojan-activity; sid:2044190; rev:3; metadata:attack_target Client_Endpoint, created_at 2022_07_23, deployment Perimeter, deployment SSLDecrypt, deprecation_reason Duplicate, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_05_03, former_sid 2851962;)