The ctl_getitem method in ntpd in ntp-4.2.8p6 before 4.2.8p11 allows remote attackers to cause a denial of service (out-of-bounds read) via a crafted mode 6 packet with a ntpd instance from 4.2.8p6 through 4.2.8p10.
packetstormsecurity.com/files/146631/Slackware-Security-Advisory-ntp-Updates.html
support.ntp.org/bin/view/Main/NtpBug3412
www.securityfocus.com/archive/1/541824/100/0/threaded
www.securityfocus.com/bid/103191
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
usn.ubuntu.com/3707-1/
www.exploit-db.com/exploits/45846/
www.synology.com/support/security/Synology_SA_18_13