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.
CVE-2016-7434
Score elevated to 8.1 because EPSS predicts 53% probability of exploitation within the next 30 days (top 1.1% of all CVEs). NVD baseline CVSS 7.5 retained for reference. Confidence: see factors.
- High exploitation likelihood — EPSS 53%
- Public exploit code is available (Exploit-DB (verified), epss top5pct, epss high, public exploit)
A fix is available — apply it.
- CVSS v3
- 7.5
- EG Score
- 8.1(high)
- EG Risk
- 67(Track)EG Risk 67/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity81% × 45%Exploitation65% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 53%
- EPSS %ILE
- 99%
- KEV
- Not listed
Published
January 13, 2017
Last Modified
June 17, 2026
References (20)
- cve@mitrehttp://nwtime.org/ntp428p9_release/
- cve@mitrehttp://support.ntp.org/bin/view/Main/NtpBug3082
- cve@mitrehttp://support.ntp.org/bin/view/Main/SecurityNotice#Recent_Vulnerabilities
- cve@mitrehttp://www.securityfocus.com/bid/94448
- cve@mitrehttp://www.securitytracker.com/id/1037354
- cve@mitrehttps://bto.bluecoat.com/security-advisory/sa139
- cve@mitrehttps://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03706en_us
- cve@mitrehttps://security.FreeBSD.org/advisories/FreeBSD-SA-16:39.ntp.asc
- cve@mitrehttps://www.exploit-db.com/exploits/40806/
- cve@mitrehttps://www.kb.cert.org/vuls/id/633847
- af854a3a-2127-422b-91ae-364da2661108http://nwtime.org/ntp428p9_release/
- af854a3a-2127-422b-91ae-364da2661108http://support.ntp.org/bin/view/Main/NtpBug3082
- af854a3a-2127-422b-91ae-364da2661108http://support.ntp.org/bin/view/Main/SecurityNotice#Recent_Vulnerabilities
- af854a3a-2127-422b-91ae-364da2661108http://www.securityfocus.com/bid/94448
- af854a3a-2127-422b-91ae-364da2661108http://www.securitytracker.com/id/1037354
Patch Availability(1)
| Vendor / Ecosystem | Fixed in / Patch | Released | Source |
|---|---|---|---|
| ubuntu | ntp (1:4.2.8p9+dfsg-2ubuntu1.1) @ zesty | 2026-05-22 | ubuntu |
Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.
Affected Packages
(1 across 1 ecosystem)
Debian:11(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| ntp | — | 1:4.2.8p9+dfsg-1 | — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
All Vendor Advisories
(1)
Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.
Data Freshness Timeline
(refreshed 5× in last 7d / 19× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
Showing the most recent 100 of 120 total refreshes for this CVE.
- 2026-09-24 13:59 UTCEPSS rescore
- 2026-09-23 13:41 UTCEPSS rescore
- 2026-09-19 15:35 UTCEPSS rescore
- 2026-09-18 19:22 UTCEPSS rescore
- 2026-09-18 17:50 UTCOSV refresh
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- 2026-09-01 13:48 UTCEPSS rescore
- 2026-09-01 03:31 UTCEPSS rescore
- 2026-08-30 21:04 UTCOSV refresh
- 2026-08-28 21:35 UTCEPSS rescore
- 2026-08-26 14:41 UTCEPSS rescore
- 2026-08-25 13:44 UTCEPSS rescore
- 2026-08-21 23:44 UTCEPSS rescore
- 2026-08-19 16:59 UTCEPSS rescore
- 2026-08-18 13:43 UTCEPSS rescore
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- 2026-08-16 02:10 UTCEPSS rescore
- 2026-08-15 01:25 UTCEPSS rescore
- 2026-08-14 07:59 UTCOSV refresh
- 2026-08-12 13:46 UTCEPSS rescore
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- 2026-08-08 16:32 UTCEPSS rescore
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- 2026-07-30 16:24 UTCEPSS rescore
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- 2026-07-30 01:26 UTCEPSS rescore
- 2026-07-29 15:37 UTCOSV refresh
- 2026-07-28 15:31 UTCEPSS rescore
- 2026-07-26 14:50 UTCEPSS rescore
- 2026-07-25 14:13 UTCEPSS rescore
- 2026-07-24 14:13 UTCEPSS rescore
- 2026-07-23 14:15 UTCEPSS rescore
- 2026-07-23 01:24 UTCEG score recompute▲ 0.60
- 2026-07-22 22:03 UTCEG score recompute
- 2026-07-22 14:04 UTCEPSS rescore
- 2026-07-21 15:21 UTCEPSS rescore
- 2026-07-21 15:21 UTCEPSS rescore
- 2026-07-20 17:04 UTCEPSS rescore
- 2026-07-19 14:28 UTCEPSS rescore
- 2026-07-19 14:28 UTCEPSS rescore
- 2026-07-19 02:26 UTCEPSS rescore
- 2026-07-19 02:26 UTCEPSS rescore
- 2026-07-16 16:59 UTCEPSS rescore
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- 2026-07-15 16:54 UTCEPSS rescore
- 2026-07-15 16:54 UTCEPSS rescore
- 2026-07-15 01:56 UTCEPSS rescore
- 2026-07-13 22:26 UTCEPSS rescore
- 2026-07-13 06:09 UTCEPSS rescore
- 2026-07-12 05:43 UTCEPSS rescore
- 2026-07-12 05:43 UTCEPSS rescore
- 2026-07-12 05:11 UTCOSV refresh
- 2026-07-11 08:24 UTCEPSS rescore
- 2026-07-09 19:06 UTCEPSS rescore
- 2026-07-07 13:42 UTCEPSS rescore
- 2026-07-06 02:20 UTCEPSS rescore
- 2026-07-06 02:20 UTCEPSS rescore
- 2026-07-04 06:28 UTCEPSS rescore
- 2026-07-01 15:02 UTCEPSS rescore
- 2026-06-28 04:53 UTCEPSS rescore
- 2026-06-27 03:05 UTCEPSS rescore
- 2026-06-25 13:47 UTCEPSS rescore
- 2026-06-24 14:02 UTCEPSS rescore
- 2026-06-23 21:30 UTCEPSS rescore
- 2026-06-23 11:00 UTCOSV refresh
- 2026-06-22 14:23 UTCEPSS rescore
- 2026-06-21 14:54 UTCEPSS rescore
- 2026-06-21 14:54 UTCEPSS rescore
- 2026-06-21 01:57 UTCEPSS rescore
- 2026-06-21 01:57 UTCEPSS rescore
- 2026-06-18 17:50 UTCEPSS rescore
- 2026-06-18 17:50 UTCEPSS rescore
- 2026-06-17 17:50 UTCEPSS rescore
- 2026-06-17 17:50 UTCEPSS rescore
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- 2026-06-15 17:45 UTCEPSS rescore
- 2026-06-14 23:14 UTCEPSS rescore
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- 2026-06-13 22:57 UTCEPSS rescore
- 2026-06-13 22:57 UTCEPSS rescore
- 2026-06-12 23:09 UTCEPSS rescore
- 2026-06-06 13:45 UTCEPSS rescore
- 2026-06-06 13:45 UTCEPSS rescore
- 2026-06-06 12:40 UTCOSV refresh
- 2026-06-05 22:44 UTCEPSS rescore
- 2026-06-05 06:08 UTCEPSS rescore
- 2026-06-05 06:08 UTCEPSS rescore
Publicly available exploits
(3 references)Working exploit code is in the public domain (2 GitHub PoCs) (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.
- Open source ↗GitHub PoCshekkbuilder/CVE-2016-7434First seen Nov 27, 2016
- GitHub PoCopsxcq/exploit-CVE-2016-7434First seen Nov 22, 2016
NTPD remote DOS exploit and vulnerable container
Open source ↗ - Exploit-DBEDB-40806✓ verifiedFirst seen Nov 21, 2016
NTP 4.2.8p8 - Denial of Service
Open source ↗
Related CVEs(same product + same vendor + same CWE)
Same product
10 shownDebian:11:ntp
- CVE-2018-12327EG 9.8EPSS p98CRITICAL
- CVE-2018-7183EG 9.8EPSS p96CRITICAL
- CVE-2015-7871EG 9.8EPSS p100CRITICAL
- CVE-2015-7853EG 9.8EPSS p96CRITICAL
- CVE-2015-7705EG 9.8EPSS p96CRITICAL
- CVE-2015-7854EG 8.8EPSS p97HIGH
- CVE-2015-7849EG 8.8EPSS p97HIGH
- CVE-2017-6460EG 8.8HIGH
- CVE-2017-6458EG 8.8EPSS p94HIGH
- CVE-2016-4957NVD 7.5EG 7.9EPSS p99HIGH
Same vendor
10 shownubuntu:USN-3349-1
- CVE-2017-6460EG 8.8HIGH
- CVE-2017-6458EG 8.8EPSS p94HIGH
- CVE-2017-6462EG 7.8HIGH
- CVE-2016-7426EG 7.5EPSS p96HIGH
- CVE-2017-6464EG 6.5EPSS p92MEDIUM
- CVE-2017-6463EG 6.5EPSS p92MEDIUM
- CVE-2016-9310EG 6.5EPSS p96MEDIUM
- CVE-2016-9042EG 5.9EPSS p90MEDIUM
- CVE-2016-2519EG 5.9EPSS p94MEDIUM
- CVE-2016-9311EG 5.9EPSS p96MEDIUM
Same CWE
10 shownCWE-20
- CVE-2016-7431EG 5.3EPSS p95MEDIUM
- CVE-2016-7791EG 9.8EPSS p90CRITICAL
- CVE-2016-7790EG 9.8EPSS p90CRITICAL
- CVE-2016-8442EG 7.8HIGH
- CVE-2016-8437EG 9.8CRITICAL
- CVE-2016-9147EG 7.5EPSS p98HIGH
- CVE-2016-9131NVD 7.5EG 7.8EPSS p99HIGH
- CVE-2016-9247EG 5.9MEDIUM
- CVE-2016-8106EG 5.9EPSS p92MEDIUM
- CVE-2016-7998EG 8.8EPSS p96HIGH
Frequently asked(5)
What is CVE-2016-7434?
When was CVE-2016-7434 disclosed?
Is CVE-2016-7434 actively exploited?
What is the CVSS score of CVE-2016-7434?
How do I remediate CVE-2016-7434?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2016-7434
Is Your Infrastructure Affected by CVE-2016-7434?
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