CVE-2026-46426 PUBLISHED

Budibase: Unrestricted Upload of File with Dangerous Type

Assigner: GitHub_M
Reserved: 13.05.2026 Published: 27.05.2026 Updated: 27.05.2026

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.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N
CVSS Score: 7.6

Product Status

Vendor Budibase
Product budibase
Versions
  • Version < 3.38.2 is affected

References

Problem Types

  • CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') CWE
  • CWE-434: Unrestricted Upload of File with Dangerous Type CWE