alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Parallax CnC Activity (set) M16"; flow:established,to_server; content:"|a0 cd 78 e6|"; startswith; fast_pattern; content:"|ff fc 36|"; distance:1; within:3; flowbits:set,ET.Parallax-16; flowbits:noalert; reference:md5,36439a5f029df1777b51a34bd454b9d2; classtype:command-and-control; sid:2034432; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_11_11, deployment Perimeter, malware_family Parallax, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_11_11;)