Budibase: Missing Cache Invalidation on Public API Role Unassignment Allows Revoked Users to Retain Privileges for Up to 1 Hour

Exploitation

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

CVSS

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

EPSS

• CVE-2026-46424: 0.16% estimated exploitation activity in the next 30 days; percentile 5.53 (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 The public API role unassignment endpoint (POST /api/public/v1/roles/unassign) updates user documents in CouchDB but does not invalidate the corresponding Redis user cache entries. Because the authentication middleware resolves user identity and permissions from this cache (TTL: 3600 seconds), a user whose admin, builder, or app-level roles have been revoked via the public API retains those privileges for up to 1 hour. Details The root cause is an inconsistency between the UserDB.save() and UserDB.bulkUpdate() code paths. Vulnerable path — packages/pro/src/sdk/publicApi/roles.ts:49-75: bulkUpdate delegates to bulkUpdateGlobalUsers() at packages/backend-core/src/users/users.ts:82-85: This writes directly to CouchDB with no cache invalidation. Correct path — packages/backend-core/src/users/db.ts:355 (used by admin UI): Cache configuration — packages/backend-core/src/cache/user.ts:11: Authentication middleware — packages/backend-core/src/middleware/authenticated.ts:153-160:…

Published by the source

19 May 2026, 16:30 UTC

Last modified by the source

10 Sep 2026, 03:50 UTC

Source last checked

26 Oct 2026, 12:53 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-6vp2-6r7m-2jvx

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-6vp2-6r7m-2jvx

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# Patch Next advisory brief: CVE-2026-46424

Advisory: Budibase: Missing Cache Invalidation on Public API Role Unassignment Allows Revoked Users to Retain Privileges for Up to 1 Hour
IDs: CVE-2026-46424, GHSA-6vp2-6r7m-2jvx
Record: https://patchnext.com/advisories/cve-2026-46424 (revision 2, source checked 26 Oct 2026, 12:53 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 4.2)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @budibase/backend-core 3.38.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @budibase/backend-core: affected < 3.38.2; fixed in 3.38.2

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

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on @budibase/backend-core.
- 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-6vp2-6r7m-2jvx (OSV record GHSA-6vp2-6r7m-2jvx lists affected ranges: npm @budibase/backend-core >=0 <3.38.2 (fixed))
- Verified: https://github.com/advisories/GHSA-6vp2-6r7m-2jvx (GitHub-reviewed advisory GHSA-6vp2-6r7m-2jvx lists affected ranges: npm @budibase/backend-core >=0 <3.38.2)

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