ntpd in ntp 4.2.x before 4.2.8p7 and 4.3.x before 4.3.92 allows authenticated users that know the private symmetric key to create arbitrarily-many ephemeral associations in order to win the clock selection of ntpd and modify a victim’s clock via a Sybil attack. This issue exists because of an incomplete fix for CVE-2016-1549.
packetstormsecurity.com/files/146631/Slackware-Security-Advisory-ntp-Updates.html
support.ntp.org/bin/view/Main/NtpBug3415
www.securityfocus.com/archive/1/541824/100/0/threaded
www.securityfocus.com/bid/103194
bugzilla.redhat.com/show_bug.cgi?id=1550214
security.FreeBSD.org/advisories/FreeBSD-SA-18:02.ntp.asc
security.gentoo.org/glsa/201805-12
security.netapp.com/advisory/ntap-20180626-0001/
support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03962en_us
www.synology.com/support/security/Synology_SA_18_13