CVE-2026-73601

Flowise versions before 3.1.3 contain a remote code execution vulnerability in the Custom MCP node when CUSTOM_MCP_PROTOCOL is set to stdio, allowing authenticated users to execute arbitrary commands by manipulating environment variables and command arguments. Attackers can abuse PYTHONWARNINGS and BROWSER environment variables with python3, or leverage the root working directory with node to bypass validation and execute system commands.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-g98q-rm45-q9h8	Vendor Advisory
https://www.vulncheck.com/advisories/flowise-before-remote-code-execution-via-custom-mcp	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:flowiseai:flowise:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-08-13 12:17

Updated : 2026-09-04 19:33

NVD link : CVE-2026-73601

Mitre link : CVE-2026-73601

CVE.ORG link : CVE-2026-73601

JSON object : View

Products Affected

flowiseai

flowise

CWE

CWE-95

Improper Neutralization of Directives in Dynamically Evaluated Code ('Eval Injection')

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