HIGH · 7.5

CVE-2026-32934

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 QUI...

Vulnerability Description

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.

CVSS Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH

Affected Products

VendorProductVersions
Coredns.IoCoredns< 1.14.3

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-32934?

CVE-2026-32934 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 QUI...

How severe is CVE-2026-32934?

CVE-2026-32934 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-32934?

Check the references section above for vendor advisories and patch information. Affected products include: Coredns.Io Coredns.