What’s Vulnerable › Vulnerabilities

CVE-2026-45021: Kuma: Default kuma-cp leaks admin token cross-origin via CORS wildcard + LocalhostIsAdmin

• Severity: medium (CVSS 5.1 v4.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-05-28 · updated 2026-10-25
• Weakness: CWE-346

Description

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.

Affected products

• kumahq kuma: before 2.7.25; from 2.9.0, < 2.9.15; from 2.11.0, < 2.11.13; from 2.12.0, < 2.12.10; from 2.13.0, < 2.13.5

References

• 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

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