Bug 2568717 (CVE-2026-123576)

Summary: CVE-2026-123576 hickory-dns: hickory-dns: Denial of Service via incomplete DNS-over-QUIC requests
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerability-draftAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
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Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Hickory DNS. A remote attacker can cause a Denial of Service (DoS) by exhausting server memory. By opening numerous connections and sending incomplete DNS-over-QUIC (DNS over the QUIC transport protocol) requests with large length prefixes, pre-allocated memory buffers persist without timing out, depleting available system memory and disrupting server availability.
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Description OSIDB Bzimport 2026-11-08 02:01:55 UTC
Hickory DNS 0.24.0 through 0.26.1 contains a memory exhaustion vulnerability that allows remote attackers to consume server resources by sending incomplete DNS-over-QUIC request bodies. Attackers can open many connections and send only large length prefixes, causing pre-allocated buffers to persist without timeout and exhausting server memory.