Medium 6.8Published Oct 5, 2015

CVE-2014-9751The read_network_packet function in ntp_io.c in ntpd in NTP 4.x before 4.2.8p1 on Linux and OS X does not properly determine whether a source IP address is an IPv6 loopback address, which makes it ea…

Updated under an hour ago (Nov 2, 2026, 3:00 AM ET)

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No exploitation reported and no EPSS estimate yet.

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The read_network_packet function in ntp_io.c in ntpd in NTP 4.x before 4.2.8p1 on Linux and OS X does not properly determine whether a source IP address is an IPv6 loopback address, which makes it easier for remote attackers to spoof restricted packets, and read or write to the runtime state, by leveraging the ability to reach the ntpd machine's network interface with a packet from the ::1 address.

CVSS: 6.8 MEDIUM (v2.0, NVD)AV:N/AC:M/Au:N/C:P/I:P/A:P
Weakness (CWE): CWE-20
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Modified
Record last updated: Jun 16, 2026
First seen by InfoSec Signals: Nov 1, 2026

Affected products

Affected products

ntp ntp ntp:ntp	from 4.2.0 before 4.2.8; 4.2.8	NVD
redhat enterprise_linux_desktop redhat:enterprise_linux_desktop	6.0	NVD
redhat enterprise_linux_server redhat:enterprise_linux_server	6.0	NVD
redhat enterprise_linux_workstation redhat:enterprise_linux_workstation	6.0	NVD
debian debian_linux debian:debian_linux	7.0; 8.0; 9.0	NVD
oracle linux oracle:linux	7	NVD

References

References

http://bugs.ntp.org/show_bug.cgi?id=2672	issue-tracking, patch, vendor-advisory
http://rhn.redhat.com/errata/RHSA-2015-1459.html	third-party-advisory
http://support.ntp.org/bin/view/Main/SecurityNotice#December_2014_NTP_Security_Vulne	vendor-advisory
http://www.debian.org/security/2015/dsa-3388	third-party-advisory
http://www.kb.cert.org/vuls/id/852879	third-party-advisory, us-government-resource
http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html	third-party-advisory
http://www.securityfocus.com/bid/72584	third-party-advisory, vdb-entry
https://bugzilla.redhat.com/show_bug.cgi?id=1184572	issue-tracking, third-party-advisory
https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03886en_us	third-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.