alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Win32/Kribat-A Downloader Activity"; flow:established,to_server; http.method; content:"GET"; http.uri; content:".php"; endswith; http.user_agent; content:"Command"; startswith; endswith; fast_pattern; http.header_names; to_lowercase; content:!"|0d 0a|referer|0d 0a|"; content:!"|0d 0a|accept"; reference:md5,78184ca66e1774598b96188f977f0687; classtype:trojan-activity; sid:2027024; rev:7; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2019_03_01, deployment Perimeter, deprecation_reason Age, malware_family Win32_Kribat_A, performance_impact Low, confidence High, signature_severity Major, updated_at 2024_05_01, reviewed_at 2023_12_19;)