RCE in Budibase

CVE-2026-31818

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.

Vulnerability class: SSRF (Server-Side Request Forgery)

EPSS: 0.004 (30.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.6 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-31818?
CVE-2026-31818 is a critical-severity vulnerability in Budibase, classified under Server-Side Request Forgery (SSRF). CVSS score: 9.6/10. Published 2026-04-03.
How severe is CVE-2026-31818?
Critical severity. CVSS v3 base score is 9.6 out of 10.