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CVE-2016-4953
ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (ephemeral-association demobilization) by sending a…
High7.5EPSS 17.2%
- Published
- Updated
- Reserved
- Assigned by
- mitre
Description
ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (ephemeral-association demobilization) by sending a spoofed crypto-NAK packet with incorrect authentication data at a certain time.
Timeline
ID reserved
By mitre
- 43 days later
· 43 days later
Published
- 8 years later
· 8 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 17.2% · top 2.9% of all CVEs (8 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Weakness
Affected products
n/a
- affected n/a
References (32)
- SUSE-SU-2016:1602 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- 91010 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- openSUSE-SU-2016:1583 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- FreeBSD-SA-16:24 (opens in a new tab)vendor-advisoryx_refsource_FREEBSDx_transferred
- SUSE-SU-2016:1912 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03757en_us (opens in a new tab)x_refsource_CONFIRMx_transferred
- http://support.ntp.org/bin/view/Main/NtpBug3045 (opens in a new tab)x_refsource_CONFIRMx_transferred
- 1036037 (opens in a new tab)vdb-entryx_refsource_SECTRACKx_transferred
- SUSE-SU-2016:1584 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html (opens in a new tab)x_refsource_CONFIRMx_transferred
- SUSE-SU-2016:2094 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- VU#321640 (opens in a new tab)third-party-advisoryx_refsource_CERT-VNx_transferred
- http://support.ntp.org/bin/view/Main/SecurityNotice (opens in a new tab)x_refsource_CONFIRMx_transferred
- http://bugs.ntp.org/3045 (opens in a new tab)x_refsource_CONFIRMx_transferred
- openSUSE-SU-2016:1636 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- SUSE-SU-2016:1563 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- GLSA-201607-15 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
- http://packetstormsecurity.com/files/137321/Slackware-Security-Advisory-ntp-Updates.html (opens in a new tab)x_refsource_MISCx_transferred
- 20160603 Multiple Vulnerabilities in Network Time Protocol Daemon Affecting Cisco Products: June 2016 (opens in a new tab)vendor-advisoryx_refsource_CISCOx_transferred
- 20170607 [security bulletin] HPESBHF03757 rev.1 - HPE Network Products including Comware 5 and Comware 7 running NTP, Remote Denial of Service (DoS) (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
- http://packetstormsecurity.com/files/137322/FreeBSD-Security-Advisory-FreeBSD-SA-16-24.ntp.html (opens in a new tab)x_refsource_MISCx_transferred
- SUSE-SU-2016:1568 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- 20160604 [slackware-security] ntp (SSA:2016-155-01) (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
- 20170607 [security bulletin] HPESBHF03757 rev.1 - HPE Network Products including Comware 5 and Comware 7 running NTP, Remote Denial of Service (DoS) (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
- 20160604 FreeBSD Security Advisory FreeBSD-SA-16:24.ntp (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
- VU#321640 (opens in a new tab)third-party-advisoryx_refsource_CERT-VNx_transferred
- 20160604 [slackware-security] ntp (SSA:2016-155-01) (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
- 20160604 FreeBSD Security Advisory FreeBSD-SA-16:24.ntp (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
- https://cert-portal.siemens.com/productcert/pdf/ssa-497656.pdf (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://us-cert.cisa.gov/ics/advisories/icsa-21-103-11 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://cert-portal.siemens.com/productcert/pdf/ssa-211752.pdf (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://us-cert.cisa.gov/ics/advisories/icsa-21-159-11 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2016-4953)Record last updated .