CVE-2017-6463: Input Validation

Published Mar 20, 2017
·
Updated

A vulnerability found in the NTP server allows an authenticated remote attacker to crash the daemon by sending an invalid setting via the :config directive. The unpeer option expects a number or an address as an argument. In case the value is "0", a segmentation fault occurs.

Affects: All versions of ntp, up to but not including ntp-4.2.8p10, and ntp-4.3.0 up to, but not including ntp-4.3.94.

Mitigation:

Properly monitor your ntpd instances, and auto-restart ntpd (without -g) if it stops running.

Other sources

NTP before 4.2.8p10 and 4.3.x before 4.3.94 allows remote authenticated users to cause a denial of service (daemon crash) via an invalid setting in a :config directive, related to the unpeer option.

Launchpad

ntp. Multiple issues were addressed by updating to version 4.2.8p10

Credit

Cure53, Matthew Van Gundy(Cisco)

Affected Software

99 affected componentsFixes available
redhat/ntp<4.2.8
4.2.8
redhat/ntp<4.3.94
4.3.94
debian/ntp
1:4.2.8p15+dfsg-1
Apple macOS High Sierra<10.13
10.13
NTP ntp=4.2.8-p9
NTP ntp=4.3.0
NTP ntp=4.3.1
NTP ntp=4.3.2
NTP ntp=4.3.3
NTP ntp=4.3.4
NTP ntp=4.3.5
NTP ntp=4.3.6
NTP ntp=4.3.7
NTP ntp=4.3.8
NTP ntp=4.3.9
NTP ntp=4.3.10
NTP ntp=4.3.11
NTP ntp=4.3.12
NTP ntp=4.3.13
NTP ntp=4.3.14
NTP ntp=4.3.15
NTP ntp=4.3.16
NTP ntp=4.3.17
NTP ntp=4.3.18
NTP ntp=4.3.19
NTP ntp=4.3.20
NTP ntp=4.3.21
NTP ntp=4.3.22
NTP ntp=4.3.23
NTP ntp=4.3.24
NTP ntp=4.3.25
NTP ntp=4.3.26
NTP ntp=4.3.27
NTP ntp=4.3.28
NTP ntp=4.3.29
NTP ntp=4.3.30
NTP ntp=4.3.31
NTP ntp=4.3.32
NTP ntp=4.3.33
NTP ntp=4.3.34
NTP ntp=4.3.35
NTP ntp=4.3.36
NTP ntp=4.3.37
NTP ntp=4.3.38
NTP ntp=4.3.39
NTP ntp=4.3.40
NTP ntp=4.3.41
NTP ntp=4.3.42
NTP ntp=4.3.43
NTP ntp=4.3.44
NTP ntp=4.3.45
NTP ntp=4.3.46
NTP ntp=4.3.47
NTP ntp=4.3.48
NTP ntp=4.3.49
NTP ntp=4.3.50
NTP ntp=4.3.51
NTP ntp=4.3.52
NTP ntp=4.3.53
NTP ntp=4.3.54
NTP ntp=4.3.55
NTP ntp=4.3.56
NTP ntp=4.3.57
NTP ntp=4.3.58
NTP ntp=4.3.59
NTP ntp=4.3.60
NTP ntp=4.3.61
NTP ntp=4.3.62
NTP ntp=4.3.63
NTP ntp=4.3.64
NTP ntp=4.3.65
NTP ntp=4.3.66
NTP ntp=4.3.67
NTP ntp=4.3.68
NTP ntp=4.3.69
NTP ntp=4.3.70
NTP ntp=4.3.71
NTP ntp=4.3.72
NTP ntp=4.3.73
NTP ntp=4.3.74
NTP ntp=4.3.75
NTP ntp=4.3.76
NTP ntp=4.3.77
NTP ntp=4.3.78
NTP ntp=4.3.79
NTP ntp=4.3.80
NTP ntp=4.3.81
NTP ntp=4.3.82
NTP ntp=4.3.83
NTP ntp=4.3.84
NTP ntp=4.3.85
NTP ntp=4.3.86
NTP ntp=4.3.87
NTP ntp=4.3.88
NTP ntp=4.3.89
NTP ntp=4.3.90
NTP ntp=4.3.91
NTP ntp=4.3.92
NTP ntp=4.3.93

Event History

Mar 27, 2017
CVE Published
via MITRE·05:00 PM
Data Sourced
via MITRE·05:00 PM
Description
Data Sourced
via NVD·05:59 PM
DescriptionSeverityWeaknessAffected Software
Feb 21, 2026
Data Sourced
via Ubuntu·06:27 PM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Launchpad·06:28 PM
Description

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2017-6463?

CVE-2017-6463 has a CVSS base score that indicates a medium severity vulnerability affecting NTP implementations.

2

How do I fix CVE-2017-6463?

To resolve CVE-2017-6463, update your NTP server to version 4.2.8p10 or later, or version 4.3.94 or later.

3

What versions of NTP are affected by CVE-2017-6463?

CVE-2017-6463 affects NTP versions 4.2.8 before p10 and all versions 4.3.x up to and including 4.3.93.

4

Who can exploit CVE-2017-6463?

An authenticated remote attacker can exploit CVE-2017-6463 by sending an invalid argument through the :config directive.

5

What is the impact of CVE-2017-6463?

The impact of CVE-2017-6463 is a denial of service due to a segmentation fault in the NTP daemon when processing an invalid setting.

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