http://support.ntp.org/bin/view/Main/NtpBug3389 A vulnerability found in the NTP server makes it possible for an authenticated remote user to crash ntpd via a malformed mode configuration directive. Affects: All versions of NTP-4, up to but not including ntp-4.2.8p10, and ntp-4.3.0 up to, but not including ntp-4.3.94. https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2017-6464
