alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Baldr Stealer Checkin M2"; flow:established,to_server; http.method; content:"POST"; http.uri; content:".php"; endswith; http.request_body; content:"Content-Disposition|3a 20|form-data|3b 20|name=|22|file|22 3b 20|filename=|22|Encrypted.zip|22 0d 0a|Content-Type|3a 20|application/octet-stream|0d 0a 0d 0a|"; fast_pattern; content:!"PK"; within:25; http.header_names; content:!"Referer"; content:!"User-Agent"; content:!"Accept"; reference:md5,216a00647603b66967cda5d91638f18a; classtype:command-and-control; sid:2027273; rev:5; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2019_04_24, deployment Perimeter, deprecation_reason Age, malware_family BALDR, performance_impact Low, confidence High, signature_severity Major, updated_at 2023_12_19, reviewed_at 2023_12_19;)