alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE MSIL/Agent.DNL Server Response Task (whoami)"; flow:established,to_client; http.content_type; content:"application/json|3b|"; startswith; file.data; content:"|7b 22|command|22 3a 22|d2hvYW1p|22 7d|"; bsize:22; fast_pattern; http.header_names; content:"|0d 0a|Content-Type|0d 0a|Date|0d 0a|Content-Length|0d 0a 0d 0a|"; bsize:40; reference:md5,a6828081717974a89792548e1e31f29a; reference:url,twitter.com/fr0s7_/status/1428326979527381000; classtype:command-and-control; sid:2033744; rev:2; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_08_19, deployment Perimeter, malware_family MSIL_Agent_DNL, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_08_19;)