NTP is one of the oldest Internet protocols still in use (since before 1985).
NTP was originally designed by David L. Mills of the University of Delaware, who still maintains it with a team of volunteers.
Only a few security problems have been identified in the reference implementation of the NTP codebase in its 25+ year history.[7][8]
[…] no security vulnerabilities have ever been reported that have been traced to the NTP specification.[9]
[…] there are no known high-risk vulnerabilities in the current released software.[10]`
(bold emphasis is mine)
