alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE MSIL/G1 Stealer/GravityRAT Requesting Payload"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"?Value=13&idPayload="; fast_pattern; http.header_names; content:!"Referer"; reference:md5,783a48640c0776932fc81925962f273b; reference:url,blog.talosintelligence.com/2018/04/gravityrat-two-year-evolution-of-apt.html; classtype:trojan-activity; sid:2025539; rev:2; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2018_04_26, deployment Perimeter, malware_family GravityRAT, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_08_25;)