SSRF in Budibase

CVE-2026-73410

Budibase is an open-source low-code platform. Prior to 3.40.0, packages/backend-core/src/utils/outboundFetch.ts pinned a validated address through a Node agent, but the REST integration used getDispatcher from packages/backend-core/src/utils/fetch.ts, causing undici to ignore that agent and resolve the hostname again. A builder could use DNS rebinding to make packages/server/src/integrations/rest.ts connect to an internal address after a public address passed validation, with full response access and arbitrary REST methods. The fix adds createPinnedLookup support to the undici dispatcher and passes the validated address to custom fetch implementations. This issue is fixed in version 3.40.0.

Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.003 (18.5th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 18th percentile — 18.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-73410: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-73410?
CVE-2026-73410 is a high-severity vulnerability in Budibase, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 8.5/10. Published 2026-08-17.
How severe is CVE-2026-73410?
High severity. CVSS v3 base score is 8.5 out of 10.