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CVE-2016-4953

Published: Jul 5, 2016Updated: May 6, 2026 Sources: CVE List NVD csafCWE-287
NVD MITRE
7.5CVSSHIGH
EPSS Score
17.2%
Top 3.3%
CISA KEV
Not in KEV
Exploits
2 Known
Remediation
Patch Available

Description

ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (ephemeral-association demobilization) by sending a spoofed crypto-NAK packet with incorrect authentication data at a certain time.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
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-287

Affected Products

n/an/a
ntpntp
On-prem
Networking Infrastructure / dns-dhcp-ntp
solarisoracle
OS
Operating Systems / unix-bsd
managersuse
On-premOS
Operating Systems / linux-distro
manager proxysuse
On-premNetwork Device
Networking Infrastructure / load-balancer-proxy
ntposs-projectNetworking Infrastructureaka ntp daemon
oraclecommercialUSDatabasesaka oracle corp.
susecommercialDEOperating Systems
and 8 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

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
Workaround Available

MITRE ATT&CK

2 techniques
Initial Access
View detailed technique mapping

References

http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00028.html
lists.opensuse.org
http://www.securityfocus.com/bid/91010
securityfocus.com
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00023.html
lists.opensuse.org
and 39 more references View all →

Timeline

Published
Jul 5, 2016
Last Updated
May 6, 2026

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