Research · Apr 9, 2026 · ZeroDay Catalog
Critical Remote Code Execution Vulnerability in Marimo
A serious remote code execution vulnerability has been identified in Marimo, affecting versions prior to 0.23.0, allowing unauthenticated access to system commands.
What changed
A critical vulnerability has been discovered in Marimo, a reactive Python notebook, prior to version 0.23.0. This vulnerability allows unauthenticated attackers to execute arbitrary system commands through the terminal WebSocket endpoint.
The flaw stems from the /terminal/ws endpoint, which lacks proper authentication validation, enabling attackers to gain a full PTY shell without any authentication checks.
Who is affected
The vulnerability impacts users of Marimo versions prior to 0.23.0, particularly those utilizing the terminal WebSocket feature.
Organizations that rely on Marimo for interactive Python notebook functionalities are at risk of unauthorized command execution.
- CoreWeave, the vendor of Marimo.
- Developers and data scientists using Marimo for Python notebook applications.
- Companies integrating Marimo into their data processing workflows.
- Any organization that has not updated to version 0.23.0 or later.
What to do
It is crucial for all users of Marimo to upgrade to version 0.23.0 or later immediately to mitigate the risk associated with this vulnerability.
In addition, organizations should review their security policies regarding the use of WebSocket endpoints and ensure that proper authentication mechanisms are in place.
- Update Marimo to version 0.23.0 or later.
- Conduct a security assessment of systems utilizing Marimo.
- Implement additional security measures for WebSocket endpoints.