CVE-2016-4955

5.9 MEDIUM
Published: July 05, 2016 Modified: May 06, 2026
View on NVD

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
http://bugs.ntp.org/3043
Source: cve@mitre.org
Issue Tracking Vendor Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00018.html
Source: cve@mitre.org
Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00020.html
Source: cve@mitre.org
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00023.html
Source: cve@mitre.org
Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00024.html
Source: cve@mitre.org
Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00028.html
Source: cve@mitre.org
Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00040.html
Source: cve@mitre.org
Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-07/msg00026.html
Source: cve@mitre.org
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00042.html
Source: cve@mitre.org
http://packetstormsecurity.com/files/137321/Slackware-Security-Advisory-ntp-Updates.html
Source: cve@mitre.org
http://packetstormsecurity.com/files/137322/FreeBSD-Security-Advisory-FreeBSD-SA-16-24.ntp.html
Source: cve@mitre.org
http://support.ntp.org/bin/view/Main/NtpBug3043
Source: cve@mitre.org
Patch Vendor Advisory
http://support.ntp.org/bin/view/Main/SecurityNotice
Source: cve@mitre.org
Release Notes Vendor Advisory
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160603-ntpd
Source: cve@mitre.org
http://www.kb.cert.org/vuls/id/321640
Source: cve@mitre.org
Third Party Advisory US Government Resource
http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html
Source: cve@mitre.org
Third Party Advisory
http://www.securityfocus.com/archive/1/538599/100/0/threaded
Source: cve@mitre.org
http://www.securityfocus.com/archive/1/538600/100/0/threaded
Source: cve@mitre.org
http://www.securityfocus.com/archive/1/archive/1/538599/100/0/threaded
Source: cve@mitre.org
http://www.securityfocus.com/archive/1/archive/1/538600/100/0/threaded
Source: cve@mitre.org
http://www.securityfocus.com/bid/91007
Source: cve@mitre.org
Third Party Advisory VDB Entry
http://www.securitytracker.com/id/1036037
Source: cve@mitre.org
Third Party Advisory VDB Entry
http://www.ubuntu.com/usn/USN-3096-1
Source: cve@mitre.org
https://cert-portal.siemens.com/productcert/pdf/ssa-211752.pdf
Source: cve@mitre.org
Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K3EYJQHJZ2KTVQ7ICEFHXTLZ36MRASWX/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ORAMN3Q7TVJ54MBYF75XCJOE3DP7LYHT/
Source: cve@mitre.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WNWGCQLW2VY72NIUYMJOCAKJKTXHDUK2/
Source: cve@mitre.org
https://security.FreeBSD.org/advisories/FreeBSD-SA-16:24.ntp.asc
Source: cve@mitre.org
Third Party Advisory
https://security.gentoo.org/glsa/201607-15
Source: cve@mitre.org
Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-159-11
Source: cve@mitre.org
https://www.kb.cert.org/vuls/id/321640
Source: cve@mitre.org
http://bugs.ntp.org/3043
Source: af854a3a-2127-422b-91ae-364da2661108
Issue Tracking Vendor Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00018.html
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00020.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00023.html
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00024.html
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00028.html
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00040.html
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-07/msg00026.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00042.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://packetstormsecurity.com/files/137321/Slackware-Security-Advisory-ntp-Updates.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://packetstormsecurity.com/files/137322/FreeBSD-Security-Advisory-FreeBSD-SA-16-24.ntp.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://support.ntp.org/bin/view/Main/NtpBug3043
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Vendor Advisory
http://support.ntp.org/bin/view/Main/SecurityNotice
Source: af854a3a-2127-422b-91ae-364da2661108
Release Notes Vendor Advisory
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160603-ntpd
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.kb.cert.org/vuls/id/321640
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory US Government Resource
http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
http://www.securityfocus.com/archive/1/538599/100/0/threaded
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.securityfocus.com/archive/1/538600/100/0/threaded
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.securityfocus.com/archive/1/archive/1/538599/100/0/threaded
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.securityfocus.com/archive/1/archive/1/538600/100/0/threaded
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.securityfocus.com/bid/91007
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory VDB Entry
http://www.securitytracker.com/id/1036037
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory VDB Entry
http://www.ubuntu.com/usn/USN-3096-1
Source: af854a3a-2127-422b-91ae-364da2661108
https://cert-portal.siemens.com/productcert/pdf/ssa-211752.pdf
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K3EYJQHJZ2KTVQ7ICEFHXTLZ36MRASWX/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ORAMN3Q7TVJ54MBYF75XCJOE3DP7LYHT/
Source: af854a3a-2127-422b-91ae-364da2661108
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WNWGCQLW2VY72NIUYMJOCAKJKTXHDUK2/
Source: af854a3a-2127-422b-91ae-364da2661108
https://security.FreeBSD.org/advisories/FreeBSD-SA-16:24.ntp.asc
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://security.gentoo.org/glsa/201607-15
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-159-11
Source: af854a3a-2127-422b-91ae-364da2661108
https://www.kb.cert.org/vuls/id/321640
Source: af854a3a-2127-422b-91ae-364da2661108

62 reference(s) from NVD

Quick Stats

CVSS v3 Score
5.9 / 10.0
EPSS (Exploit Probability)
1.7%
83th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

CWE-362

Affected Vendors

novell opensuse ntp suse siemens oracle

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