Budibase: Webhook schema endpoint authorization bypass allows unauthenticated mutation of webhook and automation schema

Exploitation

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

CVSS

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

EPSS

• CVE-2026-48151: 0.22% estimated exploitation activity in the next 30 days; percentile 13.10 (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.

The webhook schema-building endpoint is registered under builderRoutes, but the generic authorization middleware skips authorization for all paths matching /api/webhooks/schema. As a result, an unauthenticated caller can update the body schema for a known webhook and mutate the corresponding automation trigger output schema. Details The route appears to be builder-only: - packages/server/src/api/routes/webhook.ts:5-9 However, webhook endpoint detection explicitly includes schema: - packages/server/src/middleware/utils.ts:3-9 The authorization middleware bypasses all webhook endpoints before checking ctx.user or permissions: - packages/server/src/middleware/authorized.ts:90-99 The bypassed controller writes attacker-derived schema data to the webhook and automation trigger outputs: - packages/server/src/api/controllers/webhook.ts:56-83 The route grouping suggests builder authorization was intended, but the global webhook bypass removes it. PoC Non-destructive validation approach: 1.…

Published by the source

12 Jun 2026, 18:28 UTC

Last modified by the source

10 Sep 2026, 03:50 UTC

Source last checked

26 Oct 2026, 12:55 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-qhv3-wjg8-6fx6

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-qhv3-wjg8-6fx6

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# Patch Next advisory brief: CVE-2026-48151

Advisory: Budibase: Webhook schema endpoint authorization bypass allows unauthenticated mutation of webhook and automation schema
IDs: CVE-2026-48151, GHSA-qhv3-wjg8-6fx6
Record: https://patchnext.com/advisories/cve-2026-48151 (revision 2, source checked 26 Oct 2026, 12:55 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @budibase/server 3.39.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @budibase/server: affected < 3.39.0; fixed in 3.39.0

## 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
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/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-qhv3-wjg8-6fx6 (OSV record GHSA-qhv3-wjg8-6fx6 lists affected ranges: npm @budibase/server >=0 <3.39.0 (fixed))
- Verified: https://github.com/advisories/GHSA-qhv3-wjg8-6fx6 (GitHub-reviewed advisory GHSA-qhv3-wjg8-6fx6 lists affected ranges: npm @budibase/server >=0 <3.39.0)

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