CVE-2026-35579

CoreDNS is a DNS server written in Go. In versions prior to 1.14.3, the gRPC, QUIC, DoH, and DoH3 transport implementations incorrectly handle TSIG authentication. For gRPC and QUIC, the server checks whether the TSIG key name exists in the configuration but never calls dns.TsigVerify to validate...

CoreDNS has TSIG authentication bypass on gRPC and QUIC transports

Summary The gRPC, QUIC, DoH, and DoH3 transports in CoreDNS incorrectly handle TSIG authentication. For gRPC and QUIC, CoreDNS checks whether the TSIG key name exists in the config, but does not actually verify the TSIG HMAC. If the key name matches, tsigStatus remains nil and the tsig plugin...

GHSA-VP29-5652-4FW9 CoreDNS has TSIG authentication bypass on gRPC and QUIC transports

Summary The gRPC, QUIC, DoH, and DoH3 transports in CoreDNS incorrectly handle TSIG authentication. For gRPC and QUIC, CoreDNS checks whether the TSIG key name exists in the config, but does not actually verify the TSIG HMAC. If the key name matches, tsigStatus remains nil and the tsig plugin...

CoreDNS has TSIG authentication bypass on DoT, DoH, DoH3, DoQ, and gRPC

Summary CoreDNS' tsig plugin can be bypassed on non-plain-DNS transports because it trusts the transport writer's TsigStatus instead of performing verification itself. In the attached PoC, plain DNS/TCP correctly rejects an invalid TSIG NOTAUTH, while the same invalid-TSIG request is accepted ove...