Rule History

alert dns $HOME_NET any -> any any (msg:"ET MALWARE Linux/B1txor20 Backdoor Related Domain in DNS Lookup"; dns.query; dotprefix; content:".webserv.systems"; nocase; endswith; reference:url,blog.netlab.360.com/b1txor20-use-of-dns-tunneling_cn/; classtype:command-and-control; sid:2035458; rev:1; metadata:attack_target Client_Endpoint, created_at 2022_03_15, deployment Perimeter, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2022_03_15;)