CVE-2016-2517

Description

NTP before 4.2.8p7 and 4.3.x before 4.3.92 allows remote attackers to cause a denial of service (prevent subsequent authentication) by leveraging knowledge of the controlkey or requestkey and sending a crafted packet to ntpd, which changes the value of trustedkey, controlkey, or requestkey. NOTE: this vulnerability exists because of a CVE-2016-2516 regression.

Category

5.3
CVSS
Severity: Medium
CVSS 3.0 •
CVSS 2.0 •
EPSS 4.55% Top 15%
Vendor Advisory FreeBSD.org Vendor Advisory gentoo.org Vendor Advisory ntp.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
http://support.ntp.org/bin/view/Main/NtpBug3010 vendor advisory
http://www.securityfocus.com/bid/88189 third party advisory vdb entry
https://www.kb.cert.org/vuls/id/718152 third party advisory us government resource
http://www.securitytracker.com/id/1035705 vdb entry
http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html third party advisory
https://security.netapp.com/advisory/ntap-20171004-0002/
https://security.FreeBSD.org/advisories/FreeBSD-SA-16:16.ntp.asc vendor advisory
https://security.gentoo.org/glsa/201607-15 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2016-2517?
CVE-2016-2517 has been scored as a medium severity vulnerability.
How to fix CVE-2016-2517?
To fix CVE-2016-2517, 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-2016-2517 being actively exploited in the wild?
It is possible that CVE-2016-2517 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~5% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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