Bug 2466863 (CVE-2026-32934) - CVE-2026-32934 coredns: github.com/coredns/coredns: CoreDNS: Denial of Service due to unbounded resource growth in DNS-over-QUIC (DoQ) stream handling
Summary: CVE-2026-32934 coredns: github.com/coredns/coredns: CoreDNS: Denial of Servic...
Keywords:
Status: NEW
Alias: CVE-2026-32934
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-05-05 20:01 UTC by OSIDB Bzimport
Modified: 2026-05-29 12:11 UTC (History)
5 users (show)

Fixed In Version:
Clone Of:
Environment:
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Embargoed:


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Description OSIDB Bzimport 2026-05-05 20:01:58 UTC
CoreDNS is a DNS server that chains plugins. In versions prior to 1.14.3, the DNS-over-QUIC (DoQ) server can be driven into unbounded goroutine and memory growth by a remote client that opens many QUIC streams and sends only 1 byte per stream. When the worker pool is full, CoreDNS still spawns a goroutine per accepted stream to wait for a worker token. Additionally, active workers block indefinitely in io.ReadFull() with no per-stream read deadline, allowing an attacker to pin all workers by sending a single byte so the read blocks waiting for the second byte of the DoQ length prefix. This enables an unauthenticated remote attacker to cause memory exhaustion and OOM-kill. This issue has been fixed in version 1.14.3. No known workarounds exist.


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