alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE MalDoc/Gamaredon CnC Activity M3"; flow:established,to_server; http.method; content:"HEAD"; http.uri; content:"/DESKTOP-"; startswith; fast_pattern; http.user_agent; content:"Microsoft Office Existence Discovery"; bsize:36; reference:md5,a0f20cd73ab21c559431425a99543a1c; reference:url,twitter.com/Cyber0verload/status/1641096737694547970; classtype:trojan-activity; sid:2044829; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2023_03_29, deployment Perimeter, confidence High, signature_severity Major, tag Gamaredon, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_03_29;)