Node.js Users Beware of Path Traversal Vulnerability

CVSScvssV3_0: 7.9

Node.js is a popular JavaScript runtime environment used for building server-side and networking applications. Unfortunately, a path traversal vulnerability was discovered in the experimental permission model feature of Node.js versions 20 and 21.

The permission model aims to protect against path traversal attacks by sanitizing paths given by users. However, researchers found that by modifying internal Buffer objects, they could manipulate the results of the path sanitization process. This allowed traversing directories outside the intended scope, compromising the security of the file system.

A path traversal flaw like this could enable a malicious attacker to access restricted files they shouldn’t normally see. They may be able to view sensitive configuration files or even plant malware on the system.

If you rely on the experimental permission model in your Node.js app, it’s recommended to upgrade to the latest version right away after patches are released. You can also avoid using untrusted data for filesystem operations as a precaution. Staying on top of security updates for the frameworks you use is key to protecting your applications and users.

While still experimental, this serves as a reminder for developers to handle paths carefully to prevent unintended access to parts of the filesystem. Securing user input will be important if the permission model graduates from experimental status.