CVE-2016-4954: Race Condition

Published Jul 5, 2016
·
Updated

The processpacket function in ntpproto.c in ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (peer-variable modification) by sending spoofed packets from many source IP addresses in a certain scenario, as demonstrated by triggering an incorrect leap indication.

Affected Software

44 affected components
Siemens TIM 4R-IE (incl. SIPLUS NET variants)
Siemens TIM 4R-IE DNP3 (incl. SIPLUS NET variants)
Siemens SIMATIC NET CP 443-1 OPC UA
NTP ntp>=4.2.0<4.2.8
NTP ntp>=4.3.0<4.3.93
NTP ntp=4.2.8
NTP ntp=4.2.8-p1
NTP ntp=4.2.8-p1-beta1
NTP ntp=4.2.8-p1-beta2
NTP ntp=4.2.8-p1-beta3
NTP ntp=4.2.8-p1-beta4
NTP ntp=4.2.8-p1-beta5
NTP ntp=4.2.8-p1-rc1
NTP ntp=4.2.8-p1-rc2
NTP ntp=4.2.8-p2
NTP ntp=4.2.8-p2-rc1
NTP ntp=4.2.8-p2-rc2
NTP ntp=4.2.8-p2-rc3
NTP ntp=4.2.8-p3
NTP ntp=4.2.8-p3-rc1
NTP ntp=4.2.8-p3-rc2
NTP ntp=4.2.8-p3-rc3
NTP ntp=4.2.8-p4
NTP ntp=4.2.8-p5
NTP ntp=4.2.8-p6
NTP ntp=4.2.8-p7
Oracle Solaris=10
Oracle Solaris=11.3
SUSE Manager=2.1
SUSE Manager Proxy=2.1
SUSE Openstack Cloud=5
openSUSE Leap=42.1
openSUSE openSUSE=13.2
SUSE Linux Enterprise Desktop=12-sp1
SUSE Linux Enterprise Server=11-sp2
SUSE Linux Enterprise Server=11-sp3
SUSE Linux Enterprise Server=11-sp4
SUSE Linux Enterprise Server=12-sp1
Siemens Simatic Net Cp 443-1 Opc Ua Firmware
Siemens SIMATIC NET CP 443-1 OPC UA
Siemens Tim 4r-ie Firmware
Siemens Tim 4r-ie
Siemens Tim 4r-ie Dnp3 Firmware
Siemens Tim 4r-ie Dnp3

Event History

Jul 5, 2016
CVE Published
via MITRE·01:00 AM
Data Sourced
via MITRE·01:00 AM
Description

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2016-4954?

CVE-2016-4954 is classified as a denial of service vulnerability, which can severely disrupt network time synchronization services.

2

How do I fix CVE-2016-4954?

To mitigate CVE-2016-4954, upgrade to NTP version 4.2.8p8 or later, as this version contains fixes for the vulnerability.

3

What types of systems are affected by CVE-2016-4954?

CVE-2016-4954 affects various systems running vulnerable versions of NTP, including specific Siemens products and numerous Linux distributions.

4

Can CVE-2016-4954 be exploited remotely?

Yes, CVE-2016-4954 can be exploited by remote attackers sending spoofed packets, potentially affecting multiple source IP addresses.

5

What is the result of a successful exploit of CVE-2016-4954?

A successful exploit of CVE-2016-4954 can lead to a denial of service, causing the affected NTP service to malfunction or crash.

Contact

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