Vulnerability · Published May 27, 2026 · Assigned by GitHub_M

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

High 7.6

In plain English

A high-severity cross-site scripting in budibase from Budibase. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 7% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.6High

Exploit odds (30 days)0.2%top 93.0% 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 3.38.2, 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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	budibase	3.38.2	GHSA-82rc-gxrg-v4gf

Affected products (as reported)

Vendor	Product	Versions
Budibase	budibase	< 3.38.2

Weakness: CWE-79, CWE-434 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N

References

https://github.com/Budibase/budibase/security/advisories/GHSA-82rc-gxrg-v4gf x_refsource_CONFIRM
https://github.com/Budibase/budibase/releases/tag/3.38.2 x_refsource_MISC