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.
History

Thu, 13 Aug 2026 11:45:00 +0000

Type Values Removed Values Added
Description 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.
Title Flowise before 3.1.3 Remote Code Execution via Custom MCP
First Time appeared Flowiseai
Flowiseai flowise
Weaknesses CWE-95
CPEs cpe:2.3:a:flowiseai:flowise:*:*:*:*:*:*:*:*
Vendors & Products Flowiseai
Flowiseai flowise
References
Metrics cvssV4_0

{'score': 9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-08-13T11:28:08.066Z

Reserved: 2026-08-13T11:15:12.095Z

Link: CVE-2026-73601

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-13T12:17:24.353

Modified: 2026-08-13T12:17:24.353

Link: CVE-2026-73601

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-13T13:30:17Z