High priorityDisclosed

Advisory · CVE-2026-100680

Budibase OpenAPI import reads any local file via file:// references

Budibase before 3.45.0 fails to disable external JSON reference resolution in the OpenAPI/Swagger import validator. An authenticated builder can embed file:// references in an OpenAPI specification submitted to the import endpoint and exfiltrate arbitrary local files, including environment variables carrying JWT secrets, API keys, and database credentials. Fixed in 3.45.0.

Advisory published September 26, 2026Independent summary
Vendor
Budibase
Product
Budibase
Identifier / CWE
CVE-2026-100680
CWE-200
Action timing
Immediate
ELI5

Explain it like I’m five

The import desk accepts a parts catalog and, without checking, follows any 'see the paper in the locked drawer' note written in it, then hands the contents back to whoever submitted the catalog.

SIMPLIFIED_ATTACK_PATH04 STEPS
  1. 01Crafted spec

    An authenticated builder submits an OpenAPI specification containing file:// JSON references.

  2. 02Unrestricted resolution

    The import validator resolves external references, including local file references.

  3. 03Local file read

    Arbitrary local files are read, including environment carrying JWT secrets, API keys, and database credentials.

  4. 04Exfiltration

    The file contents are returned to the builder through the import flow.

What happened

Budibase before 3.45.0 fails to disable external JSON reference resolution in the OpenAPI/Swagger import validator (CVE-2026-100680, CVSS 8.6). An authenticated builder can embed file:// references in an OpenAPI specification submitted to the import endpoint and exfiltrate arbitrary local files, including environment variables carrying JWT secrets, API keys, and database credentials. The issue is fixed in Budibase 3.45.0.

What to do

  1. Upgrade Budibase to 3.45.0 or later.
  2. Rotate JWT secrets, API keys, and database credentials that lived in the Budibase server environment.
  3. Audit OpenAPI import activity for specifications containing file:// references.
  4. Limit who holds the builder role; every builder was a potential reader of server secrets.

Management note

Import endpoints that resolve external references are file-read gadgets waiting to happen. This one hands a low-privilege builder the server’s environment, so treat the credential rotation as the real work and the upgrade as the easy part.