What’s Vulnerable › Vulnerabilities
CVE-2026-18321: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') in ntpsec
- Severity: medium (CVSS 4.7 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.1% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-07-31 · updated 2026-08-28
- Weakness: CWE-120
Description
Buffer overflow in NTPsec's Zyfer refclock allows local attacker to crash ntpd
Affected products
- ntpsec: before 1.2.5 — fixed in 1.2.5
How to fix
Upgrade to a fixed version: ntpsec 1.2.5. Check the vendor advisory for mitigations.
References
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