CVE-2026-56274

Flowise before 3.1.2 contains multiple OS command injection vulnerabilities in the Custom MCP Server feature due to incomplete command-flag validation and a regex bypass in local file access restrictions. An attacker with a Flowise account of any role, or API access with view/update permissions for chatflows, can configure a malicious MCP server to bypass the validateCommandFlags blocklist (for example, 'docker build' is not blocked, and 'npx --yes' is not blocked while only '-y' is) and the validateArgsForLocalFileAccess checks, resulting in execution of arbitrary commands on the Flowise host.

CVSS v3 9.9 CRITICAL

9.9^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.1 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-m99r-2hxc-cp3q	Exploit Third Party Advisory
https://www.vulncheck.com/advisories/flowise-remote-code-execution-via-mcp-security-bypass-in-validatecommandflags-and-validateargsforlocalfileaccess	Third Party Advisory
https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-m99r-2hxc-cp3q	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-06-23 13:16

Updated : 2026-06-25 18:39

NVD link : CVE-2026-56274

Mitre link : CVE-2026-56274

CVE.ORG link : CVE-2026-56274

JSON object : View

Products Affected

flowiseai

flowise

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

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