Bug 2509863 (CVE-2026-18321)

Summary: CVE-2026-18321 ntpsec: NTPsec: Denial of Service via buffer overflow in Zyfer refclock
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
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Priority: low    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in NTPsec. A local attacker could exploit a buffer overflow vulnerability in the Zyfer refclock component, leading to the `ntpd` daemon crashing. This could result in a denial of service (DoS), making the network time synchronization service unavailable.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2514432, 2514433    
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Description OSIDB Bzimport 2026-07-31 19:01:29 UTC
Buffer overflow in NTPsec's Zyfer refclock allows local attacker to crash ntpd