CoreDNS is a DNS server that chains plugins. In versions prior to 1.14.3, the tsig plugin can be bypassed on non-plain-DNS transports (DoT, DoH, DoH3, DoQ, and gRPC) because it trusts the transport writer's TsigStatus() instead of performing verification itself. The DoH and DoH3 writer's TsigStatus() always returns nil, the DoT server does not set TsigSecret on the dns.Server, and the DoQ and gRPC writers also unconditionally return nil. This allows an unauthenticated remote client to bypass TSIG-based authentication and access resources intended to be restricted behind a tsig require all policy. Plain DNS over TCP and UDP are not affected. This issue has been fixed in version 1.14.3.
Advisories
| Source | ID | Title |
|---|---|---|
Github GHSA |
GHSA-qhmp-q7xh-99rh | CoreDNS has TSIG authentication bypass on DoT, DoH, DoH3, DoQ, and gRPC |
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Tue, 05 May 2026 21:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Coredns.io
Coredns.io coredns |
|
| Vendors & Products |
Coredns.io
Coredns.io coredns |
Tue, 05 May 2026 19:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | CoreDNS is a DNS server that chains plugins. In versions prior to 1.14.3, the tsig plugin can be bypassed on non-plain-DNS transports (DoT, DoH, DoH3, DoQ, and gRPC) because it trusts the transport writer's TsigStatus() instead of performing verification itself. The DoH and DoH3 writer's TsigStatus() always returns nil, the DoT server does not set TsigSecret on the dns.Server, and the DoQ and gRPC writers also unconditionally return nil. This allows an unauthenticated remote client to bypass TSIG-based authentication and access resources intended to be restricted behind a tsig require all policy. Plain DNS over TCP and UDP are not affected. This issue has been fixed in version 1.14.3. | |
| Title | CoreDNS TSIG authentication bypass on encrypted DNS transports | |
| Weaknesses | CWE-303 | |
| References |
| |
| Metrics |
cvssV4_0
|
Projects
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-05-05T19:02:55.374Z
Reserved: 2026-03-17T22:16:36.721Z
Link: CVE-2026-33190
No data.
Status : Received
Published: 2026-05-05T20:16:36.167
Modified: 2026-05-05T20:16:36.167
Link: CVE-2026-33190
No data.
OpenCVE Enrichment
Updated: 2026-05-05T21:30:05Z
Weaknesses
Github GHSA