ntpd in ntp 4.2.8 before 4.2.8p15 and 4.3.x before 4.3.101 allows remote attackers to cause a denial of service (memory consumption) by sending packets, because memory is not freed in situations where a CMAC key is used and associated with a CMAC algorithm in the ntp.keys file.
Exploitability
AC:HAV:NPR:HUI:NScope
S:UImpact
A:HC:NI:N4.4/CVSS:3.1/AC:H/AV:N/A:H/C:N/I:N/PR:H/S:U/UI:N