alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE CosmicDuke Exfiltrating Data via FTP STOR"; flow:established,to_server; dsize:55<>65; content:"STOR|20|"; depth:5; pcre:"/^[a-z0-9]{1,10}[A-F0-9]+\.bin\r\n$/R"; content:".bin|0d 0a|"; fast_pattern; reference:md5,5080bc705217c614b9cbf67a679979a8; classtype:targeted-activity; sid:2023910; rev:5; metadata:created_at 2015_07_17, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_10_08;)