CVE-2026-46426
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.18%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 7.6 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N
- EPSS
- 0.18% probability · 7th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-79, CWE-434
- Source
- security-advisories@github.com
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.