CVE-2026-46426 HIGH

CVE-2026-46426: Budibase: Unrestricted Upload of File with Dangerous Type

Vendor Budibase
Product budibase
Weakness CWE-79 · XSS
Published May 27, 2026
Last update May 27, 2026

CVSS base score

7.6/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction Required
Confidentiality High
Integrity Low

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N

What the vulnerability does

01Description

Budibase is an open-source low-code platform. Prior to 3.38.2, the file upload endpoint POST /api/attachments/process does not enforce active-content restrictions for authenticated users. The checks for dangerous file extensions are conditionally wrapped inside if (isPublicUser) or if (isPublicUser || !env.SELF_HOSTED), meaning any authenticated builder can upload executable web content — SVG files with inline <script> tags, HTML pages with JavaScript, .js modules — which are then stored in the object store (MinIO/S3) with their correct MIME types. When the resulting signed URL is opened by any app user, the browser executes the payload. Impact is persistent stored XSS over all application end users. This vulnerability is fixed in 3.38.2.

Key dates

02Disclosure timeline

May 27, 2026 CVE published
May 27, 2026 Record updated