CVE-2015-7977

Name: CVE-2015-7977
Creator: NVD / NIST
Published: 2017-01-30T21:59:00.41+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.9/10EPSS 6.35%

Last modified Jun 17, 2026

CVE-2015-7977 is a medium-severity vulnerability rated 5.9/10 on the CVSS scale. ntpd in NTP before 4.2.8p6 and 4.3.x before 4.3.90 allows remote attackers to cause a denial of service (NULL pointer dereference) via a ntpdc reslist command.. EPSS estimates a 6.35% chance of exploitation in the next 30 days.

Description

ntpd in NTP before 4.2.8p6 and 4.3.x before 4.3.90 allows remote attackers to cause a denial of service (NULL pointer dereference) via a ntpdc reslist command.

Metrics

CVSS 3.1

5.9/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

6.35%

92.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-476

Affected Software

Vendor	Product	Versions
Ntp	Ntp	<= 4.2.8
Ntp	Ntp	>= 4.3.0, < 4.3.90
Ntp	Ntp	4.2.8
Oracle	Linux	6
Siemens	Tim 4r-Ie Firmware	All versions
Siemens	Tim 4r-Ie Dnp3 Firmware	All versions
Netapp	Clustered Data Ontap	All versions
Netapp	Oncommand Balance	All versions
Freebsd	Freebsd	9.3
Freebsd	Freebsd	10.1
Freebsd	Freebsd	10.2
Fedoraproject	Fedora	22
Fedoraproject	Fedora	23
Debian	Debian Linux	8.0
Debian	Debian Linux	9.0
Canonical	Ubuntu Linux	12.04
Canonical	Ubuntu Linux	14.04
Canonical	Ubuntu Linux	16.04

References

http://lists.fedoraproject.org/pipermail/package-announce/2016-February/177507.htmlThird Party Advisory
http://lists.fedoraproject.org/pipermail/package-announce/2016-January/176434.htmlThird Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-04/msg00059.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2016-04/msg00060.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00020.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00038.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00048.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2016-07/msg00026.htmlThird Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00042.htmlBroken Link
http://lists.opensuse.org/opensuse-updates/2016-05/msg00114.htmlBroken Link
http://rhn.redhat.com/errata/RHSA-2016-0780.htmlBroken Link
http://rhn.redhat.com/errata/RHSA-2016-2583.htmlBroken Link
http://support.ntp.org/bin/view/Main/NtpBug2939Vendor Advisory
http://support.ntp.org/bin/view/Main/SecurityNotice#April_2016_NTP_4_2_8p7_SecurityVendor Advisory
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160127-ntpdThird Party Advisory
http://www.debian.org/security/2016/dsa-3629Third Party Advisory
http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.htmlThird Party Advisory
http://www.securityfocus.com/bid/81815Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1034782Third Party Advisory, VDB Entry
http://www.ubuntu.com/usn/USN-3096-1Third Party Advisory
https://bto.bluecoat.com/security-advisory/sa113Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-497656.pdfThird Party Advisory
https://security.FreeBSD.org/advisories/FreeBSD-SA-16:09.ntp.ascThird Party Advisory
https://security.gentoo.org/glsa/201607-15Third Party Advisory
https://security.netapp.com/advisory/ntap-20171031-0001/Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-103-11Third Party Advisory, US Government Resource
https://www.kb.cert.org/vuls/id/718152Third Party Advisory, US Government Resource
http://lists.fedoraproject.org/pipermail/package-announce/2016-February/177507.htmlThird Party Advisory
http://lists.fedoraproject.org/pipermail/package-announce/2016-January/176434.htmlThird Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-04/msg00059.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2016-04/msg00060.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00020.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00038.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00048.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2016-07/msg00026.htmlThird Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00042.htmlBroken Link
http://lists.opensuse.org/opensuse-updates/2016-05/msg00114.htmlBroken Link
http://rhn.redhat.com/errata/RHSA-2016-0780.htmlBroken Link
http://rhn.redhat.com/errata/RHSA-2016-2583.htmlBroken Link
http://support.ntp.org/bin/view/Main/NtpBug2939Vendor Advisory
http://support.ntp.org/bin/view/Main/SecurityNotice#April_2016_NTP_4_2_8p7_SecurityVendor Advisory
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160127-ntpdThird Party Advisory
http://www.debian.org/security/2016/dsa-3629Third Party Advisory
http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.htmlThird Party Advisory
http://www.securityfocus.com/bid/81815Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1034782Third Party Advisory, VDB Entry
http://www.ubuntu.com/usn/USN-3096-1Third Party Advisory
https://bto.bluecoat.com/security-advisory/sa113Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-497656.pdfThird Party Advisory
https://security.FreeBSD.org/advisories/FreeBSD-SA-16:09.ntp.ascThird Party Advisory
https://security.gentoo.org/glsa/201607-15Third Party Advisory
https://security.netapp.com/advisory/ntap-20171031-0001/Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-103-11Third Party Advisory, US Government Resource
https://www.kb.cert.org/vuls/id/718152Third Party Advisory, US Government Resource

Timeline

Published: Jan 30, 2017
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2015-7977?

ntpd in NTP before 4.2.8p6 and 4.3.x before 4.3.90 allows remote attackers to cause a denial of service (NULL pointer dereference) via a ntpdc reslist command.

How severe is CVE-2015-7977?

CVE-2015-7977 has a CVSS score of 5.9/10 (MEDIUM severity). The EPSS model estimates a 6.35% probability of exploitation in the next 30 days.

How do I fix CVE-2015-7977?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2015-7977?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST