Bug 2568787 (CVE-2026-123577)

Summary: CVE-2026-123577 hickory-dns: Hickory DNS: Denial of Service via unbounded DoH request bodies
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. This vulnerability allows an unauthenticated remote attacker to cause a Denial of Service (DoS) by transmitting oversized request bodies over HTTP/2 or HTTP/3 to a DNS over HTTPS (DoH) server. Because incoming request sizes are not properly bounded, processing these requests consumes excessive server memory and leads to service unavailability.
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Description OSIDB Bzimport 2026-11-08 02:06:15 UTC
Hickory DNS from 0.24.0 before 0.26.2 contains a resource exhaustion vulnerability that allows remote attackers to consume server memory via unbounded DoH request bodies. Attackers can send large request bodies over HTTP/2 or HTTP/3 to a DNS over HTTP server, causing memory exhaustion and denial of service.