CVE-2026-86003

Published Sep 16, 2026

Last updated 10 days ago

Overview

Description
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.
Source
security-advisories@github.com
NVD status
Awaiting Analysis

Risk scores

CVSS 3.1

Type
Secondary
Base score
7.5
Impact score
3.6
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Severity
HIGH

Weaknesses

security-advisories@github.com
CWE-441

Social media

Hype score
Not currently trending