alert dns $HOME_NET any -> any any (msg:"ET PHISHING DNS Request to NilePhish Domain 21"; dns_query; content:"dropbox-verfy.servehttp.com"; depth:27; nocase; endswith; fast_pattern; reference:url,citizenlab.org/2017/02/nilephish-report; classtype:social-engineering; sid:2023853; rev:4; metadata:affected_product Web_Browsers, attack_target Client_Endpoint, created_at 2017_02_03, deployment Perimeter, confidence Medium, signature_severity Major, tag Phishing, updated_at 2019_09_28;)