CVE-2026-45021

Kuma is a modern Envoy-based service mesh that can run on every cloud across both Kubernetes and VMs. Prior to 2.7.25, 2.9.15, 2.11.13, 2.12.10, and 2.13.5, the default kuma-cp config leaks the admin bootstrap token and signing keys to any webpage the operator visits while the control plane is reachable from their browser. CorsAllowedDomains: [".*"] reflects any Origin, and LocalhostIsAdmin: true promotes requests from 127.0.0.1 to mesh-system:admin. A cross-origin fetch() from a malicious page returns the admin JWT and signing material. This vulnerability is fixed in 2.7.25, 2.9.15, 2.11.13, 2.12.10, and 2.13.5.

CVSS

No CVSS.

References

Link	Resource
https://github.com/kumahq/kuma/commit/8fefa8595d44eb68d922405702ed7a0826322907
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

28 May 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-28 18:16

Updated : 2026-05-28 18:56

NVD link : CVE-2026-45021

Mitre link : CVE-2026-45021

CVE.ORG link : CVE-2026-45021

JSON object : View

Products Affected

No product.

CWE

CWE-346

Origin Validation Error

CWE-942

Permissive Cross-domain Policy with Untrusted Domains

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