Improper access control in CoreDNS - CVE-2026-33489
Published: April 25, 2026
Vulnerability identifier: #VU127721
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-33489
CWE-ID: CWE-284
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: CoreDNS
Affected software:
CoreDNS
CoreDNS
Detailed vulnerability description
The vulnerability allows a remote attacker to disclose sensitive information.
The vulnerability exists due to improper access control in the transfer plugin stanza selection logic when processing AXFR or IXFR requests for a configured subzone. A remote attacker can send a zone transfer request to disclose sensitive information.
Exploitation is possible when both a parent zone and a more-specific subzone are configured and a permissive parent-zone transfer rule overrides a restrictive subzone rule due to lexicographic zone selection.
How to mitigate CVE-2026-33489
Install security update from vendor's website.