CVE-2018-7185
ntp: Unauthenticated packet can reset authenticated interleaved association
Severity
LowRed Hat Product Security
CVSS 3.0
Review impact separately from score.
Published · February 27, 2018
Updated · November 21, 2025
Description
The protocol engine in ntp 4.2.6 before 4.2.8p11 allows a remote attackers to cause a denial of service (disruption) by continually sending a packet with a zero-origin timestamp and source IP address of the "other side" of an interleaved association causing the victim ntpd to reset its association.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Remove the "xleave" option from the "peer HOST xleave" lines in your ntp.conf if it exists, to entirely disable interleaved mode.
CVSS / CWE
CVSS 3.0 · 3.1CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
CWE not specified