8.7
/ 10
HIGH
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
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.
AI Analysis
TSIG authentication bypass on encrypted DNS transports
Basic Information
ID
CVE-2026-33190
Source
GitHub_M
Published
May 5, 2026 at 19:02
Affected Product
Vendor
coredns
Product
coredns
Version
< 1.14.3
Affected Versions
coredns coredns < 1.14.3
CWE Classification
AI Assessment
AI Score
8.7 / 10
AI Severity
High
Vendor
CoreDNS
Product
CoreDNS
Version
< 1.14.3