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TI-2026-25885 Aliases CVE-2026-33489GHSA-h8mm-c463-wjq3

CoreDNS transfer plugin subzone ACL bypass via lexicographic zone comparison

Priority HIGH 75CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
Security bypass
Confidentiality · integrity · availability
High · None · None
Fix status
Partial Red Hat: 2 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-863.

Summary

CoreDNS is a DNS server that chains plugins. In versions prior to 1.14.3, the transfer plugin can select the wrong ACL stanza when both a parent zone and a more-specific subzone are configured. The longestMatch() function in plugin/transfer/transfer.go uses a lexicographic string comparison instead of an actual longest-suffix match to select the winning zone. As a result, a permissive parent-zone transfer rule can override a restrictive subzone rule depending on zone name ordering (e.g., "example.org." > "a.example.org." lexicographically). This allows an unauthorized remote client to perform AXFR/IXFR for the subzone and retrieve its full zone contents. This issue has been fixed in version 1.14.3.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00404 34th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial coredns (coredns): 1.14.3github.com/coredns/coredns (Go): 1.14.3Red Hat: 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
corednscorednsbefore 1.14.31.14.3Patch availableCNA
—github.com/coredns/coredns (Go)before 1.14.31.14.3Patch availableGHSA-h8mm-c463-wjq3
  • coredns Vendorcoredns Affected before 1.14.3 Fixed in 1.14.3 Patch available CNA
  • github.com/coredns/coredns (Go) Vendor— Affected before 1.14.3 Fixed in 1.14.3 Patch available GHSA-h8mm-c463-wjq3

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:coredns.io:coredns:*:*:*:*:*:*:*:*before 1.14.3Vulnerablecoredns
  • cpe:2.3:a:coredns.io:coredns:*:*:*:*:*:*:*:* Versions before 1.14.3 Vulnerable ·coredns

Remediation

  • Fix · CNA coredns (coredns) Fixed in 1.14.3
  • Fix · GHSA-h8mm-c463-wjq3 github.com/coredns/coredns (Go) Fixed in 1.14.3 Advisory →

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Advanced Cluster Management for Kubernetes 2AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33489
  2. 2026-10-03 Alias added: GHSA-h8mm-c463-wjq3

References

Exploit 1

Advisory 1

Other 2

  • TI-2026-25615 CoreDNS TSIG authentication bypass on encrypted DNS transports CVSS 4.0HIGH 8.7
  • TI-2026-25384 CoreDNS DoH GET path missing size validation causes CPU and memory amplification CVSS 4.0HIGH 8.7
  • TI-2026-25382 CoreDNS DNS-over-QUIC unbounded goroutine growth leads to denial of service CVSS 4.0HIGH 8.7
  • TI-2026-27682 CoreDNS TSIG authentication bypass on gRPC, QUIC, DoH, and DoH3 transports CVSS 4.0HIGH 8.2
  • TI-2026-44486 NULL pointer dereference in coredns CVSS 3.1MEDIUM 5.3
  • TI-2026-44995 CoreDNS `k8s_external` headless AXFR can emit an empty transfer batch that panics the `transfer` plugin CVSS 3.1LOW 3.7
See all 15 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences