Vulnerability · Published Jun 26, 2026 · Assigned by GitHub_M

CVE-2026-50136Budibase: Unauthenticated S3 signed upload URL generation allows arbitrary writes with stored datasource credentials

High 7.4

In plain English

A high-severity missing authentication in budibase from Budibase. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 22% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.4High
Exploit odds (30 days)0.3%top 78.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

Budibase is an open-source low-code platform. Prior to 3.39.3, the application server exposes an unauthenticated endpoint that generates S3 PutObject presigned URLs using credentials stored in a workspace datasource. The route is protected only by the recaptcha middleware and does not require authentication, table permission, datasource permission, or builder access. A public caller who knows a workspace ID and S3 datasource ID can request a signed upload URL for attacker-controlled bucket and key values. This vulnerability is fixed in 3.39.3.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
npm@budibase/server3.39.2GHSA-jj36-r9w3-3pfh

Affected products (as reported)

VendorProductVersions
Budibase budibase < 3.39.3

Weakness: CWE-306 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L

References