CVE-2026-31818 Budibase: Server-Side Request Forgery via REST Connector with Empty Default Blacklist
Attackers can exploit SSRF in Budibase's REST connector when the default IP blacklist is empty, bypassing security controls to access internal resources.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-31818?
CVE-2026-31818 is a critical server-side request forgery vulnerability in budibase, published on 3 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Budibase is an open-source low-code platform. Prior to version 3.33.4, a server-side request forgery (SSRF) vulnerability exists in Budibase's REST datasource connector. The platform's SSRF protection mechanism (IP blacklist) is rendered completely ineffective because the BLACKLIST_IPS environment variable is not set by default in any of the official deployment configurations. When this variable is empty, the blacklist function unconditionally returns false, allowing all requests through without restriction. This issue has been patched in version 3.33.4.
Which versions are affected by CVE-2026-31818?
2 open source packages ship an affected version, including @budibase/backend-core. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
@budibase/backend-core npm | All versions | 3.33.4 |
@budibase/backend-core npm | All versions | 3.33.4 |
Products include Budibase Budibase.
How do I fix CVE-2026-31818?
Upgrade @budibase/backend-core to 3.33.4 or later.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-31818 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-31818 exists.
Other vulnerabilities in budibase
- CVE-2026-54350 Budibase: Anonymous NoSQL operator injection via published-app query templates
- CVE-2026-27702 Budibase Vulnerable to Remote Code Execution via Unsafe eval() in View Filter Map Function (Budibase Cloud)
- CVE-2026-54352 Budibase: Arbitrary file read by workspace-builder via PWA-zip symlink upload
- CVE-2026-30240 Budibase PWA ZIP Upload Path Traversal Allows Reading Arbitrary Server Files Including All Environment Secrets
- CVE-2026-41428 Budibase: Authentication Bypass via Unanchored Regex in Public Endpoint Matcher — Unauthenticated Access to Protected Endpoints
Sources
Also known as GHSA-7r9j-r86q-7g45.