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CVE-2016-4955

Published: Jul 5, 2016Updated: May 6, 2026 Sources: CVE List NVD csafCWE-362
5.9MEDIUM
NVD MITRE
EPSS Score
8.8%
Top 5.5%
CISA KEV
Not in KEV
Exploits
2 Known
Remediation
Patch Available
Self-Check
OpenVAS

Description

ntpd in NTP 4.x before 4.2.8p8, when autokey is enabled, allows remote attackers to cause a denial of service (peer-variable clearing and association outage) by sending (1) a spoofed crypto-NAK packet or (2) a packet with an incorrect MAC value at a certain time.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:HPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-362

Affected Products

suse
commercial·DE
manager proxyOn-premNetwork Device
Networking Infrastructure / load-balancer-proxy
openstack cloudOn-prem
Cloud & SaaS / cloud-platform
linux enterprise desktopOn-premOS
Operating Systems / linux-distro
linux enterprise serverOn-premOS
Operating Systems / linux-distro
opensuse
oss-project·DE
leapOn-premOS
Operating Systems / linux-distro
opensuseOn-premOS
Operating Systems / linux-distro
ntp
oss-projectaka ntp daemon
ntpOn-prem
Networking Infrastructure / dns-dhcp-ntp
oracle
commercial·USaka oracle corp.
solarisOS
Operating Systems / unix-bsd
novell
commercial·USaka novell suse, suse novell
suse managerOn-prem
Operating Systems / linux-distro
siemens
commercial·DEaka siemens ag
simatic net cp 443-1 opc ua firmware
ICS / OT / IoT
and 1 more affected products View all →

Exploitability

2 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

1 technique
Privilege Escalation
View detailed technique mapping

References

http://bugs.ntp.org/3043
bugs.ntp.org
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00018.html
lists.opensuse.org
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00020.html
lists.opensuse.org
and 53 more references View all →
News mentions
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