alert tcp $EXTERNAL_NET 1024: -> $HOME_NET any (msg:"ET MALWARE MSIL/Crimson CnC Server Command (info) M3"; flow:established,to_client; dsize:18; content:"|0d 00 00 00 00|inf2o=command"; threshold:type limit,track by_dst, count 5,seconds 600; reference:md5,fdd625f11ae39b85d4c0f794e8570abe; classtype:command-and-control; sid:2036243; rev:3; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2022_04_18, deployment Perimeter, malware_family Crimson, confidence High, signature_severity Major, tag c2, updated_at 2023_10_05, reviewed_at 2023_10_05;)