alert tcp $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE MSIL/Crimson CnC Server Command (info) M1"; flow:established,from_server; dsize:17; content:"|0c 00 00 00 00|info=command"; reference:md5,50eb7ae1d3c075dfc9c9e82a9fa9caf5; reference:md5,40c9031ee6bbf2b2306420e9330727a6; classtype:command-and-control; sid:2035903; rev:2; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2015_10_07, deployment Perimeter, malware_family Crimson, performance_impact Low, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_07_26;)