CVE-2016-1547

Description

An off-path attacker can cause a preemptible client association to be demobilized in NTP 4.2.8p4 and earlier and NTPSec a5fb34b9cc89b92a8fef2f459004865c93bb7f92 by sending a crypto NAK packet to a victim client with a spoofed source address of an existing associated peer. This is true even if authentication is enabled.

Category

5.3
CVSS
Severity: Medium
CVSS 3.0 •
CVSS 2.0 •
EPSS 2.06% Top 20%
Vendor Advisory debian.org Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory FreeBSD.org Vendor Advisory gentoo.org
Affected: NTP Project NTP
Affected: NTPsec Project NTPSec
Published at:
Updated at:

References

Link Tags
http://www.securityfocus.com/bid/88276 vdb entry
http://www.debian.org/security/2016/dsa-3629 vendor advisory
http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html
https://access.redhat.com/errata/RHSA-2016:1141 vendor advisory
http://rhn.redhat.com/errata/RHSA-2016-1552.html vendor advisory
http://www.securitytracker.com/id/1035705 vdb entry
http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html
https://security.netapp.com/advisory/ntap-20171004-0002/
http://www.talosintelligence.com/reports/TALOS-2016-0081/ third party advisory technical description mitigation
https://security.FreeBSD.org/advisories/FreeBSD-SA-16:16.ntp.asc vendor advisory
https://security.gentoo.org/glsa/201607-15 vendor advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-497656.pdf
https://us-cert.cisa.gov/ics/advisories/icsa-21-103-11
https://cert-portal.siemens.com/productcert/pdf/ssa-211752.pdf
https://www.arista.com/en/support/advisories-notices/security-advisories/1332-security-advisory-19

Frequently Asked Questions

What is the severity of CVE-2016-1547?
CVE-2016-1547 has been scored as a medium severity vulnerability.
How to fix CVE-2016-1547?
To fix CVE-2016-1547, 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-2016-1547 being actively exploited in the wild?
It is possible that CVE-2016-1547 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2016-1547?
CVE-2016-1547 affects NTP Project NTP, NTPsec Project NTPSec.
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