CVE-2026-73601
CriticalCVSS 9.0Summary
Flowise before 3.1.3 contains 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.
Risk Assessment
An authenticated attacker can execute arbitrary system commands, potentially leading to full system compromise.
Recommendation
Update Flowise to version 3.1.3 or later, which includes a fix for this vulnerability.
Original NVD description (English source)
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.