Buffer overflow in NTPsec's Zyfer refclock allows local attacker to crash ntpd (CVE-2026-18321)
Buffer overflow in NTPsec's Zyfer refclock allows local attacker to crash ntpd
AI Analysis
Technical Summary
CVE-2026-18321 describes a buffer overflow vulnerability in the Zyfer refclock implementation of NTPsec. A local attacker with low privileges can trigger this overflow to cause the ntpd daemon to crash, resulting in denial of service. The vulnerability is classified under CWE-120 (Classic Buffer Overflow). There is no indication of confidentiality or integrity impact. No known exploits are reported in the wild, and no patch or remediation information is currently available.
Potential Impact
The vulnerability allows a local attacker to cause a denial of service by crashing the ntpd process. There is no impact on confidentiality or integrity according to the CVSS vector. This could disrupt time synchronization services relying on NTPsec on affected systems.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict local access to trusted users to reduce risk of exploitation.
Buffer overflow in NTPsec's Zyfer refclock allows local attacker to crash ntpd (CVE-2026-18321)
Description
Buffer overflow in NTPsec's Zyfer refclock allows local attacker to crash ntpd
CVSS v3.1
Score 4.7medium
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-18321 describes a buffer overflow vulnerability in the Zyfer refclock implementation of NTPsec. A local attacker with low privileges can trigger this overflow to cause the ntpd daemon to crash, resulting in denial of service. The vulnerability is classified under CWE-120 (Classic Buffer Overflow). There is no indication of confidentiality or integrity impact. No known exploits are reported in the wild, and no patch or remediation information is currently available.
Potential Impact
The vulnerability allows a local attacker to cause a denial of service by crashing the ntpd process. There is no impact on confidentiality or integrity according to the CVSS vector. This could disrupt time synchronization services relying on NTPsec on affected systems.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict local access to trusted users to reduce risk of exploitation.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-6978-pcpc-2c45
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-18321"]
- Ecosystems
- []
- Database Specific Severity
- MODERATE
- Cvss Version
- 3.1
Threat ID: 6a6daad6bf32cb7a34667b32
Added to database: 08/01/2026, 08:14:14 UTC
Last enriched: 08/01/2026, 08:19:42 UTC
Last updated: 08/01/2026, 22:23:49 UTC
Views: 6
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