# Ntpsec vulnerabilities

Source: https://junglewise.ai/threats/vendors/ntpsec  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Updated: 11 November 2026, 03:07 UTC. Rebuilt every hour.  
Data: https://junglewise.ai/threats/vendors/ntpsec.json  
License: CC BY 4.0 with a link back

Junglewise Threat Intelligence has tracked 7 vulnerabilities in Ntpsec: 0 in the last 7 days and 5 in the last 90 days, 0 of them critical and 0 exploited in the wild. The most recent, CVE-2026-121506, was published on 3 November 2026. 5 vulnerabilities in the last four weeks, up from none in the four before. 2 technologies have a page of their own.

## Counts

- Last 7 days: 0
- Last 30 days: 5
- Last 90 days: 5
- All time: 7 (0 critical, 0 exploited in the wild)

## About Ntpsec

An open-source project maintaining a secure implementation of the Network Time Protocol.

## Latest Ntpsec vulnerabilities

- [CVE-2026-121506: NTPsec out-of-bounds read/write in NTS client extension parsing](https://junglewise.ai/threats/cve-2026-121506-an-out-of-bounds-read-and-write-in-nts-client-extension-field) (high, CVSS 7.4, published 3 Nov 2026)
- [CVE-2026-102486: NTPsec ntpd out-of-bounds read in NTS extension parsing](https://junglewise.ai/threats/cve-2026-102486-out-of-bounds-read-in-nts-extension-field-parsing-in-ntpsec-ntpd) (high, CVSS 7.5, published 21 Oct 2026)
- [CVE-2026-102485: NTPsec ntpd out-of-bounds read in Motorola Oncore driver](https://junglewise.ai/threats/cve-2026-102485-out-of-bounds-read-in-the-motorola-oncore-refclock-driver-in) (medium, CVSS 5.2, published 21 Oct 2026)
- [CVE-2026-102484: NTPsec ntpd heap buffer overflow in JJY refclock driver](https://junglewise.ai/threats/cve-2026-102484-heap-based-buffer-overflow-in-the-jjy-refclock-driver-in-ntpsec) (medium, CVSS 6.4, published 21 Oct 2026)
- [CVE-2026-102483: NTPsec ntpd denial of service in NTS Cookie handling](https://junglewise.ai/threats/cve-2026-102483-reachable-exit-in-ntpsec-ntpd-1-1-4-through-1-2-5-allows-a) (high, CVSS 7.5, published 21 Oct 2026)
- [CVE-2026-18321: NTPsec buffer overflow in Zyfer refclock](https://junglewise.ai/threats/cve-2026-18321-ntpsec-buffer-overflow-in-zyfer-refclock) (medium, CVSS 4.7, published 31 Jul 2026)
- [CVE-2016-1551: NTP and NTPsec reference clock impersonation vulnerability](https://junglewise.ai/threats/cve-2016-1551-ntp-and-ntpsec-reference-clock-impersonation-vulnerability) (low, CVSS 3.7, published 27 Jan 2017)

## Most severe Ntpsec vulnerabilities

- [CVE-2026-102486: NTPsec ntpd out-of-bounds read in NTS extension parsing](https://junglewise.ai/threats/cve-2026-102486-out-of-bounds-read-in-nts-extension-field-parsing-in-ntpsec-ntpd) (high, CVSS 7.5, published 21 Oct 2026)
- [CVE-2026-102483: NTPsec ntpd denial of service in NTS Cookie handling](https://junglewise.ai/threats/cve-2026-102483-reachable-exit-in-ntpsec-ntpd-1-1-4-through-1-2-5-allows-a) (high, CVSS 7.5, published 21 Oct 2026)
- [CVE-2026-121506: NTPsec out-of-bounds read/write in NTS client extension parsing](https://junglewise.ai/threats/cve-2026-121506-an-out-of-bounds-read-and-write-in-nts-client-extension-field) (high, CVSS 7.4, published 3 Nov 2026)
- [CVE-2026-102484: NTPsec ntpd heap buffer overflow in JJY refclock driver](https://junglewise.ai/threats/cve-2026-102484-heap-based-buffer-overflow-in-the-jjy-refclock-driver-in-ntpsec) (medium, CVSS 6.4, published 21 Oct 2026)
- [CVE-2026-102485: NTPsec ntpd out-of-bounds read in Motorola Oncore driver](https://junglewise.ai/threats/cve-2026-102485-out-of-bounds-read-in-the-motorola-oncore-refclock-driver-in) (medium, CVSS 5.2, published 21 Oct 2026)
- [CVE-2026-18321: NTPsec buffer overflow in Zyfer refclock](https://junglewise.ai/threats/cve-2026-18321-ntpsec-buffer-overflow-in-zyfer-refclock) (medium, CVSS 4.7, published 31 Jul 2026)
- [CVE-2016-1551: NTP and NTPsec reference clock impersonation vulnerability](https://junglewise.ai/threats/cve-2016-1551-ntp-and-ntpsec-reference-clock-impersonation-vulnerability) (low, CVSS 3.7, published 27 Jan 2017)

## Vulnerabilities per week

5 vulnerabilities in the last four weeks, up from none in the four before.

| Week of | Vulns | Critical | Exploited |
| --- | --- | --- | --- |
| 17 Aug 2026 | 0 | 0 | 0 |
| 24 Aug 2026 | 0 | 0 | 0 |
| 31 Aug 2026 | 0 | 0 | 0 |
| 7 Sep 2026 | 0 | 0 | 0 |
| 14 Sep 2026 | 0 | 0 | 0 |
| 21 Sep 2026 | 0 | 0 | 0 |
| 28 Sep 2026 | 0 | 0 | 0 |
| 5 Oct 2026 | 0 | 0 | 0 |
| 12 Oct 2026 | 0 | 0 | 0 |
| 19 Oct 2026 | 4 | 0 | 0 |
| 26 Oct 2026 | 0 | 0 | 0 |
| 2 Nov 2026 | 1 | 0 | 0 |
| 9 Nov 2026 | 0 | 0 | 0 |

## Ntpsec technologies

- [Ntpsec Ntpd](https://junglewise.ai/threats/technologies/ntpsec-ntpd): 4 vulnerabilities
- [NTPsec](https://junglewise.ai/threats/technologies/ntpsec): 3 vulnerabilities

## Sources

NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories. Rebuilt every hour. Cite as: Junglewise Threat Intelligence, "Ntpsec vulnerabilities", https://junglewise.ai/threats/vendors/ntpsec, 11 November 2026.