CVE-2026-18321 (GCVE-0-2026-18321)

Vulnerability from cvelistv5 – Published: 2026-07-31 18:04 – Updated: 2026-07-31 18:54
VLAI
Title
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') in ntpsec
Summary
Buffer overflow in NTPsec's Zyfer refclock allows local attacker to crash ntpd
Severity
4.7 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-120 - Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Assigner
References
Impacted products
Vendor Product Version
NTPsec ntpsec Affected: 0 , < 1.2.5 (semver)
Create a notification for this product.
Credits
Youngjoon Kim of Team Atlanta
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.