alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Subterranean Crimson Rat - Client Traffic"; flow:established,to_server; content:"crimson.universal.containers.Message"; nocase; fast_pattern; content:"java.lang.Object|3b|"; within:50; reference:url,twitter.com/James_inthe_box/status/1488987814066753538; classtype:trojan-activity; sid:2035074; rev:2; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2022_02_03, deployment Perimeter, malware_family Subterranean_Crimson, confidence High, signature_severity Major, tag RAT, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2022_02_03;)