CVE-2026-50136

Budibase: Unauthenticated S3 signed upload URL generation allows arbitrary writes with stored datasource credentials

Published Jun 26, 2026 CVSS 3.1 · 7.4 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-jj36-r9w3-3pfh Budibase: Unauthenticated S3 signed upload URL generation allows arbitrary writes with stored datasource credentials
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Budibase
Budibase budibase
Vendors & Products Budibase
Budibase budibase
Type Values Removed Values Added
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.
Title Budibase: Unauthenticated S3 signed upload URL generation allows arbitrary writes with stored datasource credentials
Weaknesses CWE-306
References
Metrics cvssV3_1

{'score': 7.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jun 27, 2026, 3:14 AM
Reserved
Jun 3, 2026, 6:49 PM
Status
Analyzed
Published
Jun 26, 2026, 9:16 PM
Modified
Jun 30, 2026, 7:40 PM