CVE-2016-7434
HighPublic exploitThe read_mru_list function in NTP before 4.2.8p9 allows remote attackers to cause a denial of service (crash) via a crafted mrulist query.
Published Jan 13, 2017 · Updated Aug 4, 2026 · Also known as DEBIAN-CVE-2016-7434, UBUNTU-CVE-2016-7434
Key Facts
Patch immediately- CVE-2016-7434 is a high-severity vulnerability (CVSS 7.5 v3.1) affecting Hpux-Ntp (Hpe), Ntp, ntp-perl (photon) and 2 more products.
- It is not listed in any known-exploited vulnerabilities catalog. Public exploit code is available.
- EPSS estimates a 53% probability of exploitation in the next 30 days.
- Fixed versions are available, including Hpux-Ntp c.4.2.8.2.0, Ntp 1:4.2.6.p5+dfsg-3ubuntu2.14.04.11, Ntp 1:4.2.8p4+dfsg-3ubuntu5.5.
- Brandefense priority: patch immediately, because it is very likely to be exploited soon.
CVSS v3.1
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS (30-day exploit likelihood)
53%
Higher than 98.9% of all scored CVEs
Exploited in the wild
No known
Not in a known-exploited catalog
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2016-7434 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
The read_mru_list function in NTP before 4.2.8p9 allows remote attackers to cause a denial of service (crash) via a crafted mrulist query.
Affected Products
567 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Hpux-NtpHpe | See advisory | c.4.2.8.2.0 |
| NtpNtp | 4.2.7-p100, 4.2.7-p101, 4.2.7-p102, 4.2.7-p103, 4.2.7-p104, 4.2.7-p105, 4.2.7-p106, 4.2.7-p107 | 4.3.94 |
| ntp-perlphoton | See advisory | NA |
| ntpstatphoton | See advisory | NA |
| ntp-docsuse | See advisory | 4.2.8p9-27.1 |
Patched Releases
Hpux-Ntp
c.4.2.8.2.0
Ntp
1:4.2.6.p5+dfsg-3ubuntu2.14.04.11, 1:4.2.8p4+dfsg-3ubuntu5.5, 1:4.2.8p9+dfsg-1, 4.2.8.p9-1, 4.2.8p9-1.1, 4.2.8p9-27.1, 4.2.8p9-46.18.1, 4.2.8p9-48.9.1, 4.2.8p9-55.1, 4.2.8p9-57.2, NA, 4.3.94
ntp-doc
4.2.8p9-1.1, 4.2.8p9-27.1, 4.2.8p9-46.18.1, 4.2.8p9-48.9.1, 4.2.8p9-55.1, 4.2.8p9-57.2
ntp-perl
NA
ntpstat
NA
Timeline
Publicly disclosed
Jan 13, 2017
Last updated
Aug 4, 2026
Weakness Type
- CWE-20 Improper Input Validation
References
- advisoryhttp://nwtime.org/ntp428p9_release/
- advisoryhttps://bto.bluecoat.com/security-advisory/sa139
- advisoryhttps://bugzilla.suse.com/1009434
- advisoryhttps://bugzilla.suse.com/1011377
- advisoryhttps://bugzilla.suse.com/1011390
FAQ
Common Questions.
The read_mru_list function in NTP before 4.2.8p9 allows remote attackers to cause a denial of service (crash) via a crafted mrulist query.
Affected: Hpux-Ntp (Hpe); Ntp versions 4.2.7-p100, 4.2.7-p101, 4.2.7-p102, 4.2.7-p103, 4.2.7-p104, 4.2.7-p105, 4.2.7-p106, 4.2.7-p107; ntp-perl (photon), among others. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including Hpux-Ntp c.4.2.8.2.0, Ntp 1:4.2.6.p5+dfsg-3ubuntu2.14.04.11, Ntp 1:4.2.8p4+dfsg-3ubuntu5.5.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.
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