CVE-2026-48147: Budibase CSRF bypass via unanchored regex in Worker matchers

CVE-2026-48147 · Severity: medium · CVSS 6.5 · Published 2026-05-27

Budibase is a low-code platform used to build internal business applications. A security flaw in the Budibase Worker component allows an attacker to bypass Cross-Site Request Forgery (CSRF) protections. By tricking a logged-in administrator into clicking a malicious link, an attacker could perform unauthorized actions such as inviting new admin users, changing global security settings, or modifying user roles, potentially leading to a full takeover of the Budibase instance.

Technologies: @budibase/backend-core (npm). Vendors: npm.

Quick answers

Is CVE-2026-48147 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-48147 being exploited in the wild.
How severe is CVE-2026-48147?
Medium severity, with a CVSS score of 6.5, published 27 May 2026.
Which products and versions are affected?
@budibase/backend-core (npm) < 3.35.4, SEMVER:introduced=0,fixed=3.35.4.
Is there a fix for CVE-2026-48147?
Yes. @budibase/backend-core (npm): upgrade to 3.35.4 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-48147 attacked?
It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-48147?
Check whether you run @budibase/backend-core (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • @budibase/backend-core (npm): upgrade to 3.35.4 or later
    npm install @budibase/backend-core@3.35.4

Technical details

The vulnerability exists in the `buildMatcherRegex` and `matches` functions within `packages/backend-core/src/middleware/matchers.ts`. Route patterns used to identify public (non-CSRF protected) endpoints are compiled into regular expressions without start (^) or end ($) anchors. Furthermore, these regexes are tested against the full request URL including the query string. An attacker can bypass CSRF, tenancy, and authentication middleware by appending a known public route pattern (e.g., `/api/global/auth/`) as a query parameter to a request targeting a protected endpoint. This allows for cross-origin state-changing operations like user management and configuration updates. The issue was addressed in version 3.35.4.

Affected products

  • Budibase Budibase < 3.35.4

Identifiers

  • CVE-2026-48147
  • GHSA-wxq7-x3qp-vcr8

Timeline

  • 2026-05-21: disclosed
  • 2026-06-12: advisory: Updated advisory published

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.