Budibase: Chat-Link Handoff Identity Confusion (Same-Tenant Account-Link CSRF)

Exploitation

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

CVSS

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

EPSS

• CVE-2026-72849: 0.16% estimated exploitation activity in the next 30 days; percentile 5.46 (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 Budibase AI chat-link handoff flow (GET/POST /api/chat-links/:instance/:token/handoff) binds an external chat identity (Slack/Discord/MS Teams/Telegram) to a Budibase user account. The confirmation endpoint is on a public route (no CSRF middleware, no auth-group gate) and the only credential it checks is a confirmationToken that is already rendered in plaintext into the HTML confirmation page the victim views. There is no binding between the confirmation token and the requester's Budibase session at preparation time, and no CSRF token on the POST. Consequently, an attacker who creates a chat-link session for their own external chat identity (or any identity they can mint in their chat platform) can induce a victim Budibase user (same tenant) to submit the confirmation POST - for example by sending them a link that auto-submits, or by XSS/CSRF on a co-tenanted page - and the victim's globalUserId becomes bound to the attacker's external identity. The attacker then sends…

Published by the source

24 Jul 2026, 21:42 UTC

Last modified by the source

14 Aug 2026, 04:12 UTC

Source last checked

26 Oct 2026, 12:58 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-pvcr-8mvp-w8qr

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-pvcr-8mvp-w8qr

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# Patch Next advisory brief: CVE-2026-72849

Advisory: Budibase: Chat-Link Handoff Identity Confusion (Same-Tenant Account-Link CSRF)
IDs: CVE-2026-72849, GHSA-pvcr-8mvp-w8qr
Record: https://patchnext.com/advisories/cve-2026-72849 (revision 2, source checked 26 Oct 2026, 12:58 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.7)
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-pvcr-8mvp-w8qr (OSV record GHSA-pvcr-8mvp-w8qr lists affected ranges: npm @budibase/server >=0 <=3.38.1)
- Verified: https://github.com/advisories/GHSA-pvcr-8mvp-w8qr (GitHub-reviewed advisory GHSA-pvcr-8mvp-w8qr lists affected ranges: npm @budibase/server >=0 <=3.38.1)

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