CVE-2026-21715

A flaw in Node.js Permission Model filesystem enforcement leaves `fs.realpathSync.native()` without the required read permission checks, while all comparable filesystem functions correctly enforce them.

As a result, code running under `–permission` with restricted `–allow-fs-read` can still use `fs.realpathSync.native()` to check file existence, resolve symlink targets, and enumerate filesystem paths outside of permitted directories.

This vulnerability affects **20.x, 22.x, 24.x, and 25.x** processes using the Permission Model where `–allow-fs-read` is intentionally restricted.

More information : https://nodejs.org/en/blog/vulnerability/march-2026-security-releases