Budibase: Builder-to-Admin Privilege Escalation via onboardUsers Endpoint Without SMTP Configuration
CVE-2026-45716 · GHSA-c54j-xp92-wh28
- Affected
- npm @budibase/worker < 3.38.1
- Fixed in
- 3.38.1· Vendor fix available
- Issue
- The POST /api/global/users/onboard endpoint is protected by workspaceBuilderOrAdmin middleware, allowing any user with builder permissions to access it. When SMTP email is not configured (the default for self-hosted Budibase instances), this endpoint bypasses the admin-restricted invite flow and directly creates users via bulkCreate, accepting arbitrary admin and builder role assignments from the request body. A builder-level user can create a new global admin account and receive the generated password in the response, achieving full privilege escalation. Details The vulnerability stems from a mismatch between the authorization level of the onboardUsers endpoint and the user-creation capabilities it exposes when SMTP is not configured. Route definition (packages/worker/src/api/routes/global/users.ts:93-109): Compare with the invite and inviteMultiple endpoints which are correctly admin-only: Controller (packages/worker/src/api/controllers/global/users.ts:601-630): Middleware…
Recommended action: Upgrade to 3.38.1 or later, then redeploy and verify.A vendor fix does not resolve your finding until you verify it in your own systems.