CVE-2026-86003

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4%, top 63% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 4 sources updated this week
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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
EG Score
7.5(medium)
EG Risk
49(Track)
EG Risk 49/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity75% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
37%
KEV
Not listed

Published

September 16, 2026

Last Modified

September 17, 2026

Advisory Details (3)

Auto-updated Sep 16, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github_release, github.
github_release Patch Available

v1.14.7

Patch available: coredns/coredns v1.14.7

https://github.com/coredns/coredns/releases/tag/v1.14.7
github_commit

commit 530b0a5ff2ad (coredns/coredns)

Fix landed in coredns/coredns commit 530b0a5ff2ad — awaiting tagged release

https://github.com/coredns/coredns/commit/530b0a5ff2ad68cc0421f10dd93568945cc671c9
github Patch Available🟡 PoC Available

CoreDNS DoH/DoQ/gRPC bypass UPDATE rejection enforced on UDP/TCP · Advisory · coredns/coredns · GitHub

https://github.com/coredns/coredns/security/advisories/GHSA-9gm5-9rfh-m6vx

Vendor Advisories for CVE-2026-86003(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
Go(1)
PackageVulnerable rangeFixed inDependents
github.com/coredns/coredns—1.14.7—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 11× in last 7d / 11× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-19 09:59 UTCVendor advisory
  2. 2026-09-18 21:29 UTCEG score recompute
  3. 2026-09-18 21:29 UTCVendor advisory
  4. 2026-09-18 19:28 UTCEPSS rescore
  5. 2026-09-18 08:59 UTCVendor advisory
  6. 2026-09-17 20:28 UTCEG score recompute
  7. 2026-09-17 19:32 UTCEPSS rescore
  8. 2026-09-17 19:31 UTCEG score recompute
  9. 2026-09-16 19:24 UTCEG score recompute
  10. 2026-09-16 18:51 UTCEG score recompute
  11. 2026-09-16 18:49 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-86003?
CVE-2026-86003 is a high vulnerability published on September 16, 2026. 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/serverquic.go, and core/dnsserver/servergrpc.go call dns.Msg.Unpack without the dns.DefaultMsgAcceptFunc request policy…
When was CVE-2026-86003 disclosed?
CVE-2026-86003 was first published in the National Vulnerability Database on September 16, 2026, with the most recent update on September 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-86003 actively exploited?
CVE-2026-86003 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 62.6% of all scored CVEs.
What is the CVSS score of CVE-2026-86003?
CVE-2026-86003 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-86003?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-86003, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-86003

Explore →

Is Your Infrastructure Affected by CVE-2026-86003?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs