alert dns $HOME_NET any -> any any (
msg:"ET PHISHING DNS Lookup for Possible Common Brand Phishing Hosted on Legitimate Windows Service";
dns.query;
content:".core.windows.net"; endswith;
pcre:"/^(?:d(?:(?:ocu|uco)sign|ropbox)|o(?:ffice365|nedrive)|adobe|gdoc)/";
pcre:!"/^onedrivecl[a-z]{2}prod[a-z]{2}[0-9]{5}\./";
classtype:policy-violation;
sid:2026486; rev:10;
metadata:affected_product Web_Browsers, attack_target Client_Endpoint, created_at 2018_10_15, deployment Perimeter, confidence Medium, signature_severity Minor, tag Phishing, updated_at 2020_11_17;
)