CVE-2016-4955

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.

Category

5.9
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 8.77% Top 10%
Vendor Advisory opensuse.org Vendor Advisory ubuntu.com Vendor Advisory fedoraproject.org Vendor Advisory opensuse.org Vendor Advisory FreeBSD.org Vendor Advisory opensuse.org Vendor Advisory fedoraproject.org Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory fedoraproject.org Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory gentoo.org Vendor Advisory cisco.com Vendor Advisory opensuse.org Vendor Advisory ntp.org Vendor Advisory ntp.org Vendor Advisory ntp.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00028.html mailing list third party advisory vendor advisory
http://www.ubuntu.com/usn/USN-3096-1 vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WNWGCQLW2VY72NIUYMJOCAKJKTXHDUK2/ vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00023.html mailing list third party advisory vendor advisory
https://security.FreeBSD.org/advisories/FreeBSD-SA-16:24.ntp.asc third party advisory vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2016-07/msg00026.html vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ORAMN3Q7TVJ54MBYF75XCJOE3DP7LYHT/ vendor advisory
http://www.securityfocus.com/bid/91007 vdb entry third party advisory
http://support.ntp.org/bin/view/Main/NtpBug3043 patch vendor advisory
http://www.securitytracker.com/id/1036037 vdb entry third party advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00024.html mailing list third party advisory vendor advisory
http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html third party advisory
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00042.html vendor advisory
http://bugs.ntp.org/3043 issue tracking vendor advisory
http://www.kb.cert.org/vuls/id/321640 third party advisory us government resource
http://support.ntp.org/bin/view/Main/SecurityNotice release notes vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K3EYJQHJZ2KTVQ7ICEFHXTLZ36MRASWX/ vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00040.html mailing list third party advisory vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00018.html mailing list third party advisory vendor advisory
https://security.gentoo.org/glsa/201607-15 third party advisory vendor advisory
http://packetstormsecurity.com/files/137321/Slackware-Security-Advisory-ntp-Updates.html
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160603-ntpd vendor advisory
http://packetstormsecurity.com/files/137322/FreeBSD-Security-Advisory-FreeBSD-SA-16-24.ntp.html
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00020.html vendor advisory
http://www.securityfocus.com/archive/1/538599/100/0/threaded mailing list
http://www.securityfocus.com/archive/1/538600/100/0/threaded mailing list
https://www.kb.cert.org/vuls/id/321640 third party advisory
http://www.securityfocus.com/archive/1/archive/1/538599/100/0/threaded mailing list
http://www.securityfocus.com/archive/1/archive/1/538600/100/0/threaded mailing list
https://cert-portal.siemens.com/productcert/pdf/ssa-211752.pdf third party advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-159-11

Frequently Asked Questions

What is the severity of CVE-2016-4955?
CVE-2016-4955 has been scored as a medium severity vulnerability.
How to fix CVE-2016-4955?
To fix CVE-2016-4955, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2016-4955 being actively exploited in the wild?
It is possible that CVE-2016-4955 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~9% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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