CVE-2015-7973

Name: CVE-2015-7973
Creator: NVD / NIST
Published: 2017-01-30T21:59:00.143+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 3.33%

Last modified Jun 17, 2026

CVE-2015-7973 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. NTP before 4.2.8p6 and 4.3.x before 4.3.90, when configured in broadcast mode, allows man-in-the-middle attackers to conduct replay attacks by sniffing the network.. EPSS estimates a 3.33% chance of exploitation in the next 30 days.

Description

NTP before 4.2.8p6 and 4.3.x before 4.3.90, when configured in broadcast mode, allows man-in-the-middle attackers to conduct replay attacks by sniffing the network.

Metrics

CVSS 3.1

6.5/10

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

EPSS Probability

3.33%

87.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-254

Affected Software

Vendor	Product	Versions
Ntp	Ntp	< 4.2.8
Ntp	Ntp	>= 4.3.0, < 4.3.90
Ntp	Ntp	4.2.8
Siemens	Tim 4r-Ie Firmware	All versions
Siemens	Tim 4r-Ie Dnp3 Firmware	All versions
Freebsd	Freebsd	>= 10.0, < 10.1
Freebsd	Freebsd	9.3
Freebsd	Freebsd	10.1
Freebsd	Freebsd	10.2
Netapp	Clustered Data Ontap	All versions
Netapp	Oncommand Balance	All versions
Canonical	Ubuntu Linux	12.04
Canonical	Ubuntu Linux	14.04
Canonical	Ubuntu Linux	16.04

References

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.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00042.htmlBroken Link
http://lists.opensuse.org/opensuse-updates/2016-05/msg00114.htmlBroken Link
http://support.ntp.org/bin/view/Main/NtpBug2935Vendor Advisory
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160127-ntpdThird Party Advisory
http://www.securityfocus.com/bid/81963Third 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://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03750en_usThird Party Advisory
https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03766en_usThird 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.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.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00042.htmlBroken Link
http://lists.opensuse.org/opensuse-updates/2016-05/msg00114.htmlBroken Link
http://support.ntp.org/bin/view/Main/NtpBug2935Vendor Advisory
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160127-ntpdThird Party Advisory
http://www.securityfocus.com/bid/81963Third 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://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03750en_usThird Party Advisory
https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03766en_usThird 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-2015-7973?

NTP before 4.2.8p6 and 4.3.x before 4.3.90, when configured in broadcast mode, allows man-in-the-middle attackers to conduct replay attacks by sniffing the network.

How severe is CVE-2015-7973?

CVE-2015-7973 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 3.33% probability of exploitation in the next 30 days.

How do I fix CVE-2015-7973?

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-2015-7973?

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

Scan your code now

Source: NVD / NIST