CVE-2026-33489: CoreDNS' transfer stanza selection uses lexicographic compare (subzone ACL bypass)

April 28, 2026 (updated May 8, 2026)

CoreDNS’ transfer plugin can select the wrong ACL stanza when both a parent zone and a more-specific subzone are configured. A permissive parent-zone transfer rule can override a restrictive subzone rule (name-dependent), allowing an unauthorized client to perform AXFR/IXFR for the subzone and retrieve its zone contents.

References

github.com/advisories/GHSA-h8mm-c463-wjq3
github.com/coredns/coredns/releases/tag/v1.14.3
github.com/coredns/coredns/security/advisories/GHSA-h8mm-c463-wjq3
nvd.nist.gov/vuln/detail/CVE-2026-33489

Code Behaviors & Features

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