CVE-2026-48147 Budibase: Unanchored Regex in `matchers.ts` Allows CSRF Bypass via Query String Injection in Budibase Worker
An unauthenticated attacker can bypass CSRF protection in Budibase Worker by injecting route patterns into the query string, allowing unauthorized state-changing actions like admin invites.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-48147?
CVE-2026-48147 is a medium-severity vulnerability in budibase, published on 27 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Budibase is an open-source low-code platform. Prior to 3.35.4, the buildMatcherRegex() / matches() functions in packages/backend-core/src/middleware/matchers.ts route patterns are compiled into unanchored regular expressions and tested against ctx.request.url, which includes the full query string. The CSRF middleware in the Budibase Worker uses this matching system to decide whether to skip CSRF token validation. An unauthenticated attacker can forge state-changing cross-origin requests against any Worker API endpoint by injecting a public route pattern into the query string, causing the CSRF middleware to skip token validation entirely. This allows actions such as sending admin invites, modifying global configuration, and managing users without a valid CSRF token. This vulnerability is fixed in 3.35.4.
Which versions are affected by CVE-2026-48147?
2 open source packages ship an affected version, including @budibase/backend-core.
| Package | Affected | Fixed in |
|---|---|---|
@budibase/backend-core npm | All versions | 3.35.4 |
@budibase/backend-core npm | All versions | 3.35.4 |
How do I fix CVE-2026-48147?
Upgrade @budibase/backend-core to 3.35.4 or later.
Is CVE-2026-48147 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-48147 exists.
Sources
Also known as GHSA-wxq7-x3qp-vcr8.