CVE-2025-59528 Scanner

Flowise is a powerful data stream processing software that is utilized by enterprises to efficiently automate data workflows and handle large volumes of data seamlessly. Often deployed in cloud environments, it enables developers to design data processing applications by providing an intuitive graphical interface. Organizations from various sectors, such as finance, healthcare, and technology, leverage Flowise to improve their operational efficiencies. The software supports integration with Node.js, allowing users to extend its functionalities by incorporating custom scripts. However, the same flexibility introduces vulnerabilities, as seen with the Remote Code Execution (RCE) issue. Regular security assessments and software updates are critical in maintaining the security posture of systems using Flowise.

The Remote Code Execution (RCE) vulnerability detected in Flowise version 3.0.5 is critically dangerous as it allows attackers to run arbitrary code. This flaw exists due to the unsafe evaluation of user inputs within the CustomMCP node's convertToValidJSONString function. When exploited, it grants attackers the capability to execute commands with Node.js privileges. Such vulnerabilities are often targeted by malicious actors to gain unauthorized access or control over a system. The security issue is severe, emphasizing the importance of adopting secure coding practices. Regular updates and user awareness can mitigate risks associated with such vulnerabilities.

The technical root of this vulnerability lies in the mishandling of user inputs in the CustomMCP node's convertToValidJSONString function. The affected endpoint is the customMCP node-load-method, which improperly processes specially crafted payloads. Attackers can execute potentially harmful scripts by sending crafted input like a request with mcpServerConfig set to execute code through child_process. Specifically, the endpoint fails to correctly sanitize user inputs, allowing for command injection and execution within the Node.js runtime environment. The ability to utilize interactsh to test the vulnerability indicates its accessibility and exploitability. Effective containment requires fixing the input validation logic within the application endpoint.

If exploited, this Remote Code Execution vulnerability can have devastating effects, leading to full system compromise. Malicious actors can gain complete control over the affected system by executing arbitrary commands. This can result in unauthorized data access, data loss, or even service disruptions across enterprise-level applications. Furthermore, exploiting such critical vulnerabilities could potentially lead to lateral movement within an organization's network, escalating cyber threats to other systems. The financial and reputational consequences for an organization can be substantial, necessitating immediate actions upon detecting this vulnerability. Preventive measures, such as backward compatibility checks and regular security updates, play a vital role in averting such severe impacts.

REFERENCES

• https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-3gcm-f6qx-ff7p
• https://nvd.nist.gov/vuln/detail/CVE-2025-59528