Skip to content
CVE Tracker
Back

CVE-2016-1547

An off-path attacker can cause a preemptible client association to be demobilized in NTP 4.2.8p4 and earlier and NTPSec…

Medium5.3EPSS 5.1%
Published
Updated
Reserved
Assigned by
certcc

Description

An off-path attacker can cause a preemptible client association to be demobilized in NTP 4.2.8p4 and earlier and NTPSec a5fb34b9cc89b92a8fef2f459004865c93bb7f92 by sending a crypto NAK packet to a victim client with a spoofed source address of an existing associated peer. This is true even if authentication is enabled.

Scores

CVSS scores of CVE-2016-1547, by who scored it
Scored byCVSSScoreVector
NVDNVD · Modified3.0Medium5.3CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS (exploitation in 30 days)
5.1% · top 7.7% of all CVEs (2 Nov 2026)

Loading the EPSS history…

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.

Weakness

Affected products

  • NTP Project · NTP

    • affected 4.2.8p3
    • affected 4.2.8p4

  • NTPsec Project · NTPSec

    • affected a5fb34b9cc89b92a8fef2f459004865c93bb7f92

References (15)

Sources

The same CVE in the primary databases and aggregators, to check against.

Record last updated .