CVE-2026-18676

The default kuma-cp configuration in Kong Mesh reveals the admin bootstrap token and signing keys to any webpage the operator visits while the control plane is reachable from their browser. Due to a CORS misconfiguration a cross-origin fetch() from a malicious page returns the admin JWT and signing material.

CVSS

No CVSS.

References

Link	Resource
https://developer.konghq.com/mesh/changelog/
https://github.com/kumahq/kuma/pull/16416
https://github.com/kumahq/kuma/pull/16423
https://github.com/kumahq/kuma/pull/16424
https://github.com/kumahq/kuma/pull/16425
https://github.com/kumahq/kuma/pull/16426
https://github.com/kumahq/kuma/pull/16427
https://github.com/kumahq/kuma/security/advisories/GHSA-3vcp-chfh-f6r2

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-12 19:17

Updated : 2026-08-31 19:22

NVD link : CVE-2026-18676

Mitre link : CVE-2026-18676

CVE.ORG link : CVE-2026-18676

JSON object : View

Products Affected

No product.

CWE

CWE-346

Origin Validation Error

CWE-942

Permissive Cross-domain Security Policy with Untrusted Domains

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