CVE-2026-86003

CoreDNS is a DNS server written in Go. Prior to 1.14.7, the DNS-over-HTTPS, DNS-over-HTTP/3, DNS-over-QUIC, and DNS-over-gRPC listeners in plugin/pkg/doh/doh.go, core/dnsserver/server_quic.go, and core/dnsserver/server_grpc.go call dns.Msg.Unpack without the dns.DefaultMsgAcceptFunc request policy used by UDP, TCP, and DNS-over-TLS. An unauthenticated client can send an RFC 2136 UPDATE that the proxy or forward plugin passes unchanged to an update-capable upstream. If that upstream trusts CoreDNS's source address or connection and does not require an attacker-unknown end-to-end TSIG, the request appears to originate from CoreDNS and can add, replace, or delete DNS records, redirect traffic, take over names, alter mail routing, or disrupt the writable zone. This issue is fixed in version 1.14.7.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/coredns/coredns/commit/530b0a5ff2ad68cc0421f10dd93568945cc671c9
https://github.com/coredns/coredns/releases/tag/v1.14.7
https://github.com/coredns/coredns/security/advisories/GHSA-9gm5-9rfh-m6vx

Configurations

No configuration.

History

16 Sep 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-16 19:17

Updated : 2026-09-24 21:24

NVD link : CVE-2026-86003

Mitre link : CVE-2026-86003

CVE.ORG link : CVE-2026-86003

JSON object : View

Products Affected

No product.

CWE

CWE-441

Unintended Proxy or Intermediary ('Confused Deputy')

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