Budibase: SSRF via DNS rebinding in the REST datasource integration

Exploitation

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

CVSS

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

EPSS

• CVE-2026-73410: 0.28% estimated exploitation activity in the next 30 days; percentile 20.56 (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's central outbound-fetch guard (fetchWithBlacklist) prevents SSRF/DNS-rebinding by resolving the target hostname, checking every resolved IP against the blacklist, and pinning the connection to the validated IP. The pin is implemented as a Node http(s).Agent (makePinnedAgent). The fix for CVE-2026-54353 relies on this pin to stop DNS rebinding. The REST datasource integration (@budibase/server) calls fetchWithBlacklist but performs the actual request with undici's fetch. undici does not support the Node agent option — it is silently ignored — and instead uses its own dispatcher, which re-resolves the hostname's DNS at connection time. As a result, the validated/pinned IP is never used on the REST datasource path, and the DNS-rebinding protection that CVE-2026-54353 added is silently defeated for the single most-used outbound path in Budibase. An authenticated user who can configure/run a REST datasource (e.g. a builder/tenant) can use a rebinding hostname (public IP…

Published by the source

24 Jul 2026, 21:44 UTC

Last modified by the source

12 Aug 2026, 19:40 UTC

Source last checked

26 Oct 2026, 13:01 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-v42f-v8xc-j435

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-v42f-v8xc-j435

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2026-73410

Advisory: Budibase: SSRF via DNS rebinding in the REST datasource integration
IDs: CVE-2026-73410, GHSA-v42f-v8xc-j435
Record: https://patchnext.com/advisories/cve-2026-73410 (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 8.5)
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-v42f-v8xc-j435 (OSV record GHSA-v42f-v8xc-j435 lists affected ranges: npm @budibase/server >=0 <=3.38.1)
- Verified: https://github.com/advisories/GHSA-v42f-v8xc-j435 (GitHub-reviewed advisory GHSA-v42f-v8xc-j435 lists affected ranges: npm @budibase/server >=0 <=3.38.1)

Commands are suggestions: review each one before running it.