Vulnerability · Published Jan 7, 2026 · Assigned by mitre
CVE-2025-67364
High 7.5
In plain English
A high-severity security flaw in the fast-filesystem-mcp package (npm). Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 51% of all known vulnerabilities).
Official description
fast-filesystem-mcp version 3.4.0 contains a critical path traversal vulnerability in its file operation tools including fast_read_file. This vulnerability arises from improper path validation that fails to resolve symbolic links to their actual physical paths. The safePath and isPathAllowed functions use path.resolve() which does not handle symlinks, allowing attackers to bypass directory access restrictions by creating symlinks within allowed directories that point to restricted system paths. When these symlinks are accessed through valid path references, the validation checks are circumvented, enabling access to unauthorized files.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | fast-filesystem-mcp | no fix listed | GHSA-j893-m93w-jwjw |
Affected products (as reported)
Weakness: CWE-24 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N