OpenFGA: Unauthenticated playground endpoint discloses preshared API key in HTML response
Date: 2026-04
Affected: go/github.com/openfga/openfga
Attack vector: info-disclosure
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2026-40293
CWE: CWE-200
CVSS: 6.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N)

### Description When OpenFGA is configured to use preshared-key authentication with the built-in playground enabled, the local server includes the preshared API key in the HTML response of the /playground endpoint. The /playground endpoint is enabled by default and does not require authentication. It is intended for local development and debugging and is not designed to be exposed to production environments. ### Am I Affected? You are affected if you meet each of the following preconditions: * You are running OpenFGA with --authn-method preshared, and * The playground is enabled, and * The playground endpoint is accessible beyond localhost or trusted networks. ### Fix Upgrade to OpenFGA v1.14.0, or disable the playground by running `./openfga run --playground-enabled=false.`


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Architectural layers (MAESTRO):