CVE-2026-31818

Critical

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.

SeverityCritical

CVSS9.6

Exploit probability—

ProductBudibase

PublishedApr 3, 2026

First seenApr 3, 2026

Weakness typeCWE-918Server-side request forgery (SSRF)CWE-1188CWE-1188

How to fix

Update

budibase budibase3.33.4 or later
@budibase/backend-core3.33.4 or later

Affected products

Product	Affected versions	Fixed in
budibase budibase	v < 3.33.4	3.33.4
@budibase/backend-corenpm	v < 3.33.4	3.33.4

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