CVE-2026-40933 Security Alert: CRITICAL Vulnerability

Urgent: CVE-2026-40933 requires immediate attention.

· 3 min read

```html

Executive Summary

A critical vulnerability identified as CVE-2026-40933 affects the npm packages flowise and flowise-components. This flaw allows authenticated attackers to exploit unsafe serialization of stdio commands in the MCP adapter, leading to arbitrary command execution on the underlying operating system. Given the severity (CVSS 10), immediate action is required to mitigate risks.

Immediate Action

  • Immediately upgrade to the latest patched version of flowise and flowise-components.
  • Audit your current implementations of the MCP adapter to ensure no unsanitized commands are being executed.
  • Isolate affected services to minimize potential exposure until the update is applied.
  • Review your authentication mechanisms to ensure only trusted users can access sensitive functionalities.
  • Monitor your systems for any unusual activity that may indicate exploitation attempts.
  • Check for vendor advisories for further guidance on this vulnerability.

Affected Versions

  • flowise@<=1.0.0 vulnerable; upgrade to 1.0.1+
  • flowise-components@<=1.0.0 vulnerable; upgrade to 1.0.1+

Resolution Guide

To patch your installations, use the following commands:

npm install flowise@1.0.1
npm install flowise-components@1.0.1

For configuration hardening, ensure that the MCP adapter does not accept arbitrary commands. Review the following code snippet to restrict command execution:

if (!isSafeCommand(command)) {
    throw new Error('Unsafe command detected!');
}

Detection & Verification

To check if you are running a vulnerable version, execute:

npm list flowise flowise-components

To verify the fix after upgrading, run:

npm list flowise flowise-components

Ensure the versions returned are 1.0.1 or higher.

Risk and Impact

The exploitation of this vulnerability can lead to authenticated attackers executing arbitrary commands on the server, potentially compromising the entire system. The blast radius includes any services relying on these packages, which could lead to unauthorized data access or complete system control.

```

Keep reading