Budibase: Basic app users can exfiltrate stored REST datasource auth by rewriting datasource base URL

published 2026-05-27 5 mo ago modified 2026-09-10 1 mo ago also GHSA-3gp5-q4jw-3v94 , EUVD-2026-32588

cvss: 8.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 17%
public exploits: 0; none known

Budibase is an open-source low-code platform. Prior to 3.39.0, the single-datasource GET and PUT routes are guarded by generic TABLE READ, not by Builder/Admin permission or datasource-specific ownership/resource checks. The built-in Basic app user role maps to the WRITE permission set, which includes table read/write and query write. A Basic user can therefore read an existing REST datasource, receive redacted authConfigs values, submit an update that changes only config.url while keeping the redacted placeholders, and trigger an existing saved relative-path REST query. During update, mergeConfigs() restores the old stored secret when it sees the redaction placeholder. During query execution, Budibase prefixes the attacker-controlled datasource config.url to the relative query path and applies the resolved stored auth headers. The result is server-side disclosure of the builder-configured REST Authorization secret to an attacker-controlled listener. This vulnerability is fixed in 3.39.0.

Patch / fix

fixed in 1

npm @budibase/server 3.39.0

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: total
Assessed: 5 mo ago (2026-05-27)

Exploit prediction

0.26% chance of exploitation in the next 30 days, higher than 17% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/Budibase/budibase/security/advisories/GHSA-3gp5-q4jw-3v94 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.1	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
GitHub	3.1	8.1	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Affected packages

ecosystem	package	affected	fixed in
npm	@budibase/server	<3.39.0	3.39.0

Affected products

Budibase budibase

Classification

Weakness

CWE-863 Incorrect Authorization

References

github.com /Budibase/budibase/security/advisories/GHSA-3gp5-q4jw-3v94
exploit, web
nvd.nist.gov /vuln/detail/CVE-2026-48152
advisory
github.com /Budibase/budibase
package

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary