alert tcp $EXTERNAL_NET 1024: -> $HOME_NET any (msg:"ET MALWARE Linux/Agent.HX CnC Activity M2"; flow:established,to_client; flowbits:isset,ET.LinuxAgent.HX; flowbits:unset,ET.LinuxAgent.HX; dsize:9; content:"beatHeart"; fast_pattern; reference:md5,3176bee52ecd305816b17fdb9db7335e; reference:url,twitter.com/michalmalik/status/1245347696065630210; classtype:command-and-control; sid:2029787; rev:2; metadata:affected_product Linux, attack_target Client_Endpoint, created_at 2020_04_01, deployment Perimeter, confidence High, signature_severity Major, updated_at 2020_04_01;)