Horizon Alert
Summary of the vulnerability and why it matters
This critical vulnerability impacts Flowise, a platform used for building AI workflows, by allowing a user with specific permissions to execute arbitrary operating system commands on the server. The issue arises from how the platform processes CSV data, enabling an attacker to inject malicious code that can lead to complete system compromise.
- Malicious CSV data can run harmful commands.
- Prevents unauthorized server control.
- Verify if this system is exposed and needs attention.
Attack Path
How an attacker could exploit the issue
An attacker can leverage a CSV Agent node within Flowise to execute arbitrary commands. By crafting a data URI within the `csvFile` parameter, an attacker can inject malicious Python code. This code, when processed by the vulnerable Pyodide execution environment, allows the attacker to break out of the Python sandbox and interact with Node.js built-in modules, ultimately leading to remote code execution on the Flowise server.
- Attacker crafts malicious CSV data.
- Vulnerable API endpoint processes the data.
- Arbitrary code execution on the server.
Live Threat
Current exploitation, exposure, and threat context
This vulnerability could allow an unauthenticated attacker to execute arbitrary operating system commands on the Flowise server when a crafted chatflow is triggered. This is possible because an attacker-controlled segment from a CSV file data URI is directly inserted into a Python code template, which is then executed. The execution environment, Pyodide, has access to JavaScript functions that can break out of the Python string, import Node.js built-in modules like `fs` and `child_process`, and perform file operations or run OS commands.
- Arbitrary code execution on the server.
- User-crafted CSV data triggers RCE.
- Compromised server and data access.
Operational Fix
Recommended remediation, mitigation, and detection steps
Real-world action for this vulnerability likely falls to the Platform Engineering or Application Development teams responsible for Flowise instances, with potential coordination from Security Operations to confirm exposure and Vendor Management if Flowise is a third-party service. The first critical step is to identify all deployed Flowise instances, determine their internet reachability, assess business criticality, and locate the accountable owners before planning remediation efforts.
- Platform or application owners should investigate.
- Verify Flowise instance exposure and criticality.
- Plan remediation based on asset risk.
