CVE-2026-32934 (GCVE-0-2026-32934)

Vulnerability from cvelistv5 – Published: 2026-05-05 19:06 – Updated: 2026-05-06 15:14
VLAI
Title
CoreDNS DNS-over-QUIC unbounded goroutine growth leads to denial of service
Summary
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.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
Impacted products
Vendor Product Version
coredns coredns Affected: < 1.14.3
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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