Arbitrary File Upload Affecting flowise package, versions <3.0.13
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applicationsSnyk Learn
Learn about Arbitrary File Upload vulnerabilities in an interactive lesson.
Start learning- Snyk IDSNYK-JS-FLOWISE-15440714
- published9 Mar 2026
- disclosed6 Mar 2026
- creditKim SooHyun
Introduced: 6 Mar 2026
NewCVE-2026-30821 (opens in a new tab)How to fix?
Upgrade flowise to version 3.0.13 or higher.
Overview
flowise is a Flowiseai Server
Affected versions of this package are vulnerable to Arbitrary File Upload via the /api/v1/attachments/:chatflowId/:chatId endpoint, which allows unauthenticated file uploads by trusting the client-supplied MIME type without verifying the actual file content or extension. An attacker can upload arbitrary files, including executable scripts or web shells, by spoofing the Content-Type header, potentially leading to remote code execution or client-side attacks such as stored script execution when files are accessed.