CVE-2026-41269: Flowise: File Upload Validation Bypass in createAttachment

CVE-2026-41269 · Severity: high · CVSS 7.1 · Published 2026-04-23

Flowise is an open-source AI workflow and chatbot builder. This vulnerability allows authenticated attackers to bypass file upload restrictions and upload malicious JavaScript files by modifying chatflow configuration settings to include the application/javascript MIME type. Successfully uploaded files can execute arbitrary commands on the server, leading to complete system compromise.

Technologies: FlowiseAI Flowise, flowise (npm). Vendors: FlowiseAI, npm.

Quick answers

Is CVE-2026-41269 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-41269 being exploited in the wild.
How severe is CVE-2026-41269?
High severity, with a CVSS score of 7.1, published 23 April 2026.
Which products and versions are affected?
flowise (npm) <= 3.0.13, SEMVER:introduced=0,fixed=3.1.0.
Is there a fix for CVE-2026-41269?
Yes. flowise (npm): upgrade to 3.1.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-41269 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-41269?
Check whether you run FlowiseAI Flowise or flowise (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • flowise (npm): upgrade to 3.1.0 or later
    npm install flowise@3.1.0

Technical details

The vulnerability is an improper file upload validation flaw (CWE-434) in the createAttachment API endpoint. The Chatflow configuration API (`/api/v1/chatflows/{CHATFLOW_ID}`) fails to validate MIME types server-side, allowing authenticated users to inject application/javascript into the allowedUploadFileTypes list. Although the frontend does not expose JavaScript as an upload option, an attacker with valid credentials can directly modify the chatbotConfig parameter to add this MIME type, then upload .js files to the `/api/v1/attachments/{CHATFLOW_ID}/{CHAT_ID}` endpoint. Once uploaded, the attacker can execute the malicious Node.js script (containing web shells or command execution payloads) if the file is accessed or loaded by the application, resulting in Remote Code Execution. This bypasses a prior patch (GHSA-35g6-rrw3-v6xc / CVE-2025-61687). A fix is available in Flowise version 3.1.0 and later.

Affected products

  • FlowiseAI Flowise <=3.0.13

Identifiers

  • CVE-2026-41269
  • GHSA-rh7v-6w34-w2rr

Timeline

  • 2026-04-15: disclosed
  • 2026-04-16: patched: Version 3.1.0 available

References

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