alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Mustang Panda APT Related Activity (Response)"; flow:established,to_client; flowbits:isset,ET.mustangpanda.numbymane; http.stat_code; content:"200"; http.header_names; content:"|0d 0a|Content-Type|0d 0a|Content-Length|0d 0a 0d 0a|"; startswith; fast_pattern; file.data; pcre:"/^[0-9a-f]{32}$/"; reference:url,twitter.com/StopMalvertisin/status/1635620870214352901; reference:url,twitter.com/t3ft3lb/status/1635597523434762240; reference:md5,15c74f8c597d2937abae779ee5ef95d7; reference:md5,821ec39800471963a4ccef10b587b8d6; classtype:trojan-activity; sid:2044640; rev:1; metadata:attack_target Client_Endpoint, created_at 2023_03_16, deployment Perimeter, deployment SSLDecrypt, malware_family MustangPanda, malware_family NUMBYMANE, performance_impact Low, confidence High, signature_severity Major, tag TA416, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_03_16; target:dest_ip;)