CVE-2025-59528 PoC — Flowise has Remote Code Execution vulnerability

Source

https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2025/CVE-2025-59528.yaml

Associated Vulnerability

Title: Flowise has Remote Code Execution vulnerability (CVE-2025-59528)
Description:Flowise is a drag & drop user interface to build a customized large language model flow. In version 3.0.5, Flowise is vulnerable to remote code execution. The CustomMCP node allows users to input configuration settings for connecting to an external MCP server. This node parses the user-provided mcpServerConfig string to build the MCP server configuration. However, during this process, it executes JavaScript code without any security validation. Specifically, inside the convertToValidJSONString function, user input is directly passed to the Function() constructor, which evaluates and executes the input as JavaScript code. Since this runs with full Node.js runtime privileges, it can access dangerous modules such as child_process and fs. This issue has been patched in version 3.0.6.

Description

Flowise 3.0.5 contains a remote code execution vulnerability caused by unsafe evaluation of user input in the CustomMCP node's convertToValidJSONString function, letting remote attackers execute arbitrary code with full Node.js privileges, exploit requires user input to be processed by the vulnerable node.

File Snapshot

Remarks

1. It is advised to access via the original source first.

2. Local POC snapshots are reserved for subscribers — if the original source is unavailable, the local mirror is part of the paid plan.

View subscription plans →