alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Mustang Panda APT Related Activity M2 (Response)"; flow:established,to_client; flowbits:isset,ET.mustangpanda.numbymane; http.stat_code; content:"200"; http.header_names; strip_pseudo_headers; to_lowercase; content:"|0d 0a|content-type|0d 0a|content-length|0d 0a 0d 0a|"; startswith; fast_pattern; http.content_len; byte_test:0,=,0,0,string,dec; reference:url,twitter.com/StopMalvertisin/status/1635620870214352901; reference:url,twitter.com/t3ft3lb/status/1635597523434762240; reference:md5,15c74f8c597d2937abae779ee5ef95d7; reference:md5,821ec39800471963a4ccef10b587b8d6; classtype:trojan-activity; sid:2044642; rev:2; metadata:attack_target Client_Endpoint, created_at 2023_03_16, deployment Perimeter, deployment SSLDecrypt, malware_family MustangPanda, malware_family NUMBYMANE, performance_impact Moderate, confidence High, signature_severity Major, tag TA416, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_26; target:dest_ip;)