8.7

CVE-2026-32934: CoreDNS DNS-over-QUIC unbounded goroutine growth leads to denial of service

Analyzed
AliasesCGA-2q54-24cv-jf6wCGA-55cp-758r-hcgwCGA-cwvr-x4vw-m4mg
Published 05-05-2026Last modified 06-05-2026

Vulnerability summary

CVE-2026-32934 is a high (CVSS 8.7) vulnerability in coredns. EPSS estimates a 0.47% chance of exploitation in the next 30 days, higher than 40.6% of scored vulnerabilities. 1 public exploit is recorded.

Priority
Prioritisepublic exploit

Public exploit (GitHub, Date unknown)

Source freshness unavailable

How is this decided?
CVSS score
8.7/10
010
High · v4.0 (CVE.org)
EPSS score
0.47%
0%100%
Low · -0.16 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits1github

Advisory lineage

Upstream 0 · Downstream 1 · Related 2
OPENSUSE-SU-2026:21483-1CGA-CJ8W-HR6G-6WVX

Timeline

  1. 05-05-2026
    PublishedVulnerability first disclosed.
  2. 06-05-2026
    Last modifiedVulnerability information updated.

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 metrics

7 scores · 5 sources · 2 versions

EPSS trend

Probability

0.47%

Chance of exploitation in the next 30 days

Percentile

41%

Versus all other CVEs

30-day change

Decrease -0.16 pp

From 0.63% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

1 found
  • githubUnverified

    Coredns

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Chainguard22 products
  • coredns-1.13All versions (No fix recorded)
  • coredns-fips-1.13All versions (No fix recorded)
  • eks-distro-coredns-1.30All versions (No fix recorded)
  • eks-distro-coredns-1.31< 1.31.43-r2
  • eks-distro-coredns-1.32< 1.32.36-r2
Wolfi5 products
  • coredns-1.13All versions (No fix recorded)
  • juicefs-1.3< 1.3.1-r14
  • k8s_gateway< 1.8.0-r1
  • kubernetes-dns-node-cache< 1.26.8-r3
  • kuma-coredns-1.13All versions (No fix recorded)
Coredns1 product
Coredns.io1 product
Github.com/coredns1 product
  • coredns< 1.14.3

5 vendors · 30 products

References

6 links