ntpd in NTP 4.x before 4.2.8p8, when autokey is enabled, allows remote attackers to cause a denial of service (peer-variable clearing and association outage) by sending (1) a spoofed crypto-NAK packet or (2) a packet with an incorrect MAC value at a certain time.
Exploitability
AV:NAC:HPR:NUI:NScope
S:UImpact
C:NI:NA:H5.9/CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H