medium
5.3
CWE
20
Advisory Published
Updated

CVE-2016-4956: Input Validation

First published: Tue Jul 05 2016(Updated: )

ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (interleaved-mode transition and time change) via a spoofed broadcast packet. NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-1548.

Credit: cve@mitre.org

Affected SoftwareAffected VersionHow to fix
Siemens Simatic Net CP 443-1 OPC UA Firmware
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 SPARC=10
Oracle Solaris SPARC=11.3
suse manager proxy=2.1
openSUSE OpenStack Cloud=5
SUSE Manager=2.1
openSUSE=42.1
openSUSE=13.2
SUSE Linux Enterprise Desktop with Beagle=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 CP 443-1 OPC UA Firmware
Siemens Simatic Net CP 443-1 OPC UA Firmware

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Reference Links

Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is the severity of CVE-2016-4956?

    The severity of CVE-2016-4956 is classified as medium, indicating it can lead to a denial of service.

  • How do I fix CVE-2016-4956?

    To fix CVE-2016-4956, you should upgrade to NTP version 4.2.8p8 or later.

  • What systems are affected by CVE-2016-4956?

    CVE-2016-4956 affects NTP version 4.x prior to 4.2.8p8 and several Siemens products.

  • What type of vulnerability is CVE-2016-4956?

    CVE-2016-4956 is a denial of service vulnerability caused by processing spoofed broadcast packets.

  • Is there a known exploit for CVE-2016-4956?

    While specific exploits may not be publicly documented, the vulnerability allows remote attackers to induce a denial of service.

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