DNS client in Microsoft Windows 8.1; Windows Server 2012 R2, Windows RT 8.1; Windows 10 Gold, 1511, and 1607; and Windows Server 2016 fails to properly process DNS queries, which allows remote attackers to obtain sensitive information via (1) convincing a workstation user to visit an untrusted webpage or (2) tricking a server into sending a DNS query to a malicious DNS server, aka "Windows DNS Query Information Disclosure Vulnerability."
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2017-0057