Budibase: Privilege escalation via public role assignment API missing app-level authorization

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

8.8 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS

• CVE-2026-73305: 0.52% estimated exploitation activity in the next 30 days; percentile 44.44 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary Budibase 3.39.19 (commit 03fbabae4) is affected by a privilege-escalation / missing-authorization flaw in the public role-assignment API. An app-scoped builder (a user who builds only specific apps — user.builder.apps = [appA], not a global builder or admin) can grant themselves builder access to ANY other app in the tenant, or assign themselves/any user an arbitrary data-plane role (e.g. ADMIN) in any app, by calling POST /api/public/v1/roles/assign. The endpoint only authorizes the two global flags (admin, builder); the per-app appBuilder and role:{appId,roleId} grant vectors are passed to the backend without any authorization check that the caller controls the target app. Reproduced in a local authorized lab using the verbatim authorization-gate and SDK logic. This is an incomplete fix of the role-assignment hardening in commit d63d1d9054 ("Inline public user global role validation"), which only ever validated the global flags. Details The issue is caused by authorization…

Published by the source

24 Jul 2026, 21:12 UTC

Last modified by the source

12 Aug 2026, 19:11 UTC

Source last checked

26 Oct 2026, 13:01 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-j9fc-w3mr-x6mv

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-j9fc-w3mr-x6mv

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# Patch Next advisory brief: CVE-2026-73305

Advisory: Budibase: Privilege escalation via public role assignment API missing app-level authorization
IDs: CVE-2026-73305, GHSA-j9fc-w3mr-x6mv
Record: https://patchnext.com/advisories/cve-2026-73305 (revision 2, source checked 26 Oct 2026, 13:01 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @budibase/server: affected <= 3.38.1

## Suggested inspection (read-only)
- `npm ls @budibase/server --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on @budibase/server.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-j9fc-w3mr-x6mv (OSV record GHSA-j9fc-w3mr-x6mv lists affected ranges: npm @budibase/server >=0 <=3.38.1)
- Verified: https://github.com/advisories/GHSA-j9fc-w3mr-x6mv (GitHub-reviewed advisory GHSA-j9fc-w3mr-x6mv lists affected ranges: npm @budibase/server >=0 <=3.38.1)

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