The vulnerability resides in the is_path_allowed function of read_file_tool/write_file_tool in geekgod382 filesystem-mcp-server 1.0.0. It allows an attacker who can reach the server to craft requests that bypass path validation, enabling traversal outside the intended directory. This flaw can lead to reading or writing arbitrary files on the host, jeopardizing confidentiality, integrity, and possibly availability if critical system files are altered. The weakness is a classic directory traversal, classified under CWE-22.

The affected product is geekgod382 filesystem-mcp-server version 1.0.0. Users running this version are vulnerable. The issue is fixed in version 1.1.0, as identified by the patch commit 45364545fc60dc80aadcd4379f08042d3d3d292e.

The CVSS score of 6.9 indicates moderate severity; the EPSS score is not available, so the probability of exploitation cannot be quantified. The vulnerability is not listed in the CISA KEV catalog, but it has been publicly disclosed and may be used by remote attackers. Since the flaw involves path traversal, the attack vector is remote, exploiting network exposed interfaces of the server.