CVE-2026-58057

Flowise before 3.1.3 validates Custom MCP stdio environment variables against a denylist using a case-sensitive comparison, so on Windows, where environment names are case-insensitive, supplying 'node_options' bypasses the NODE_OPTIONS denylist entry. An authenticated user who can configure a Custom MCP node can thereby inject NODE_OPTIONS --require and execute arbitrary code in the Flowise server context.

CVSS v3 5.0 MEDIUM

5.0^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/FlowiseAI/Flowise/pull/6471	Issue Tracking Patch
https://github.com/bikini/exploitarium/tree/main/flowise-mcp-env-case-bypass-poc	Exploit Third Party Advisory
https://www.vulncheck.com/advisories/flowise-custom-mcp-environment-variable-denylist-bypass-via-case-sensitivity	Exploit Patch Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-06-28 02:16

Updated : 2026-07-06 14:54

NVD link : CVE-2026-58057

Mitre link : CVE-2026-58057

CVE.ORG link : CVE-2026-58057

JSON object : View

Products Affected

flowiseai

flowise

CWE

CWE-178

Improper Handling of Case Sensitivity

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