alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Observed NimPlant Server Response (Inbound)"; flow:established,to_client; http.server; bsize:18; content:"NimPlant|20|C2|20|Server"; nocase; fast_pattern; reference:url,github.com/chvancooten/NimPlant; classtype:trojan-activity; sid:2044340; rev:2; metadata:attack_target Client_Endpoint, created_at 2023_02_24, deployment Perimeter, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_26; target:dest_ip;)