alert dns $HOME_NET any -> any any (msg:"ET MALWARE Group 21 CnC Domain Observed in DNS Query"; dns.query; content:"quwa-paf.servehttp.com"; nocase; endswith; classtype:domain-c2; sid:2029289; rev:3; metadata:affected_product Web_Browsers, attack_target Client_Endpoint, created_at 2020_01_16, deployment Perimeter, confidence High, signature_severity Major, tag Group21, updated_at 2020_10_27;)