alert tcp-pkt $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE ELF/RapperBot CnC Checkin M2"; flow:established,to_server; content:"|f6 b7 0b 00 14 77 35 f9 8d 6d 5d c4 bd 23 88 7e cf 5e 02 ce 54 5f e7 b1 e6 3f 2a 16 71 b6 eb 9a|"; startswith; fast_pattern; reference:url,fortinet.com/blog/threat-research/rapperbot-malware-discovery; classtype:command-and-control; sid:2037962; rev:1; metadata:affected_product Linux, attack_target Client_Endpoint, created_at 2022_08_08, deployment Perimeter, malware_family ELF_RapperBot, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2022_08_08;)