Arbitrary Command Execution in Flowise by FlowiseAI
CVE-2026-40933

10CRITICAL

Key Information:

Vendor

Flowiseai

Status
Flowise
Flowise-components
Vendor
CVE Published:
21 April 2026

What is CVE-2026-40933?

Flowise, an intuitive drag-and-drop interface for customizing large language model flows, contains a vulnerability that allows authenticated attackers to execute arbitrary commands. This arises from unsafe serialization of stdio commands in the MCP adapter prior to version 3.1.0. Users can manipulate the 'Custom MCP' configuration interface by adding an MCP with compromised stdio server commands. Although input sanitization functions like validateCommandInjection and validateArgsForLocalFileAccess exist, they failed to effectively mitigate command execution risks, permitting potential exploitation via command injection techniques. The issue has been rectified in version 3.1.0.

Affected Version(s)

Flowise < 3.1.0

flowise-components < 3.1.0

References

https://github.com/FlowiseAI/Flowise/security/advisories/...
x_refsource_CONFIRM
https://www.ox.security/blog/mcp-supply-chain-advisory-rc...
x_refsource_MISC
https://www.ox.security/blog/the-mother-of-all-ai-supply-...
x_refsource_MISC

CVSS V3.1

Score:
10
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.