CVE-2016-1547
An off-path attacker can cause a preemptible client association to be demobilized in NTP 4.2.8p4 and earlier and NTPSec a5fb34b9cc89b92a8fef2f459004865c93bb7f92 by sending a crypto NAK packet to a victim client with a spoofed source address of an existing associated peer. This is true even if authentication is enabled.
Date published : 2017-01-06
http://www.securityfocus.com/bid/88276
http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html