CVE-2026-33190 | BDVDB-2026-330503 Detail
corednscoredns
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.
Impact#
Per CVSS v4.0: confidentiality impact high, integrity impact none, availability impact none. Attack vector: network.
Weaknesses#
- CWE-303 Incorrect Implementation of Authentication Algorithm
References#
Exploit#
No public exploit known
History#
- Version 1Record published in the CVE List.
- Version 2Most recent update recorded in the CVE List.