Node.js Permissions Model Bypass via Crafted Symlinks Allowing Arbitrary File Read/Write

A vulnerability in Node.js's permissions model enables attackers to circumvent '--allow-fs-read' and '--allow-fs-write' restrictions by using manipulated relative symlink paths. This issue is present in Node.js versions 20.x, 22.x, 24.x, and 25.x. By chaining directories and symlinks, a script with access limited to the current directory can escape the designated path and access sensitive files. This behavior undermines the expected isolation and allows arbitrary reading or writing of files, potentially leading to system compromise.

Impact

Exploitation of this vulnerability could result in unauthorized access to sensitive files or arbitrary file modifications, with the potential for system compromise.

Remediation

Users can upgrade to Node.js versions 20.20.0, 22.22.0, 24.13.0, or 25.4.0 to address this vulnerability.