fkie_cve-2026-76910

Unleash is an open-source feature management platform. Prior to 8.0.3, cloneFeatureToggle and POST /api/admin/projects/:projectId/features/:featureName/clone authorize creation in the destination project but do not verify access to the source project. Because feature names are globally unique, a user with create or clone permission in one project who knows or guesses another project's feature name can copy that feature into the authorized project and inspect its strategy parameters, constraints, variants, and variant payloads. This issue is fixed in version 8.0.3.

GHSA-8xcj-9hfr-fh9j — Unleash: Clone-feature lets a user copy a feature from a project they cannot read

Affected: npm: unleash-server

### Summary

The clone-feature endpoint supports copying features across projects, but it does not verify that the caller can access the source project. A user with _create_ permissions in one project can clone a feature from another project they cannot read and then inspect the copied configuration.

This vulnerability cannot be confirmed without Enterprise access. Report is based on a circumstantial evidence in the open-source repository.

### Details `src/lib/features/feature-toggle/feature-toggle-service.ts` implements `cloneFeatureToggle`. This operation needs authorization for both sides: permission to read/copy the source feature and permission to create the destination feature.

The clone path validates permissions against the destination project, but not against the source project that owns `featureName`. Because feature names are globally unique, a caller can reference a feature outside projects they can access.

### PoC 1. Create or identify two projects: `P1` with a private or restricted feature named `secret-feature`, and `P2` where the attacker has clone/create permissions. 2. Authenticate as the attacker. 3. Send:

```http POST /api/admin/projects/P2/features/secret-feature/clone Content-Type: application/json

{ "name": "secret-feature-copy" } ```

4. Open `P2` and inspect `secret-feature-copy`. Verify if strategy parameters, constraints, variants, and variant payloads from the source feature have been copied.

### Impact Users with permissions on one project…

Most recent entries from all

fkie_cve-2026-76910

GHSA-8xcj-9hfr-fh9j — Unleash: Clone-feature lets a user copy a feature from a project they cannot read