Budibase is an open-source low-code platform. Prior to 3.39.0, /api/public/v1/roles/assign is guarded by the builderOrAdmin middleware, which passes any user who is a builder for the app id in the x-budibase-app-id header. That check admits both global builders and workspace-scoped builders (builder.apps set but builder.global unset). The controller then spreads the request body into the SDK call, and the SDK grants builder.global=true or admin.global=true on whichever user ids the caller supplies. Bob, a workspace-scoped builder with an API key, promotes himself or any other user to global admin with one POST. The whole flow is tenant-wide privilege escalation from an app-level role, available to anyone with an Enterprise license that unlocks the EXPANDED_PUBLIC_API feature. This vulnerability is fixed in 3.39.0.

Affected: npm: @budibase/server

## Summary

`/api/public/v1/roles/assign` is guarded by the `builderOrAdmin` middleware, which passes any user who is a builder for the app id in the `x-budibase-app-id` header. That check admits both global builders and workspace-scoped builders (`builder.apps` set but `builder.global` unset). The controller then spreads the request body into the SDK call, and the SDK grants `builder.global=true` or `admin.global=true` on whichever user ids the caller supplies. Bob, a workspace-scoped builder with an API key, promotes himself or any other user to global admin with one POST. The whole flow is tenant-wide privilege escalation from an app-level role, available to anyone with an Enterprise license that unlocks the `EXPANDED_PUBLIC_API` feature.

## Details

Controller (`packages/server/src/api/controllers/public/roles.ts:13-17`):

```typescript export async function assignAppBuilder(ctx: Ctx) { const { userIds, ...assignmentProps } = ctx.request.body await sdk.publicApi.roles.assign(userIds, assignmentProps) ctx.body = { data: { userIds } } } ```

Nothing filters `assignmentProps`. The request body's `builder` and `admin` keys flow directly into the SDK.

SDK (`packages/pro/src/sdk/publicApi/roles.ts:17-47`):

```typescript export async function assign(userIds: string[], opts: AssignmentOpts) { if (!(await isExpandedPublicApiEnabled())) { throw new Error("Unable to assign roles - license required.") } const users = await userDB.bulkGet(userIds) for (let user o…

Ein Angreifer kann mehrere Schwachstellen in Budibase ausnutzen, um Administratorrechte zu erlangen, Sicherheitsmaßnahmen zu umgehen, Cross-Site-Scripting-Angriffe durchzuführen, Daten zu manipulieren oder vertrauliche Informationen offenzulegen.