mcp-filesystem-server
MCP serverVerified · Rung 3Filesystem MCP server with unrestricted filesystem access and pwd-based relative paths. 13 tools for read, write, directory, and search operations. No directory allowlist: the server grants access to the entire host filesystem.
Security cap applied
Score breakdown
Based on 1 evaluation. Confidence rises as more independent tests agree.
The verdict
Functionally complete but a security non-starter for any real deployment. The server ships with unrestricted filesystem access by design: it reads /etc/passwd without error, and its startup log says 'Unrestricted filesystem access enabled'. All 13 tools work correctly. The tools themselves are well-implemented. The problem is architectural: there is no directory allowlist, no configuration option to add one, and no path validation. Any agent using this server can read or modify any file the host OS user can access. Do not deploy this in any environment where the agent might receive untrusted input, where the host has sensitive files, or where the filesystem is shared with other processes. If you need a filesystem MCP server, use the official @modelcontextprotocol/server-filesystem instead.
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Security findings
Flags from our evaluations, ordered by severity.
- High
UNRESTRICTED_FILESYSTEM_ACCESS
No directory allowlist. The server accesses any path the OS user can access. Confirmed: read_file('/etc/passwd') returns the full file contents. Startup log explicitly states 'Unrestricted filesystem access enabled'. There is no configuration option to restrict access. Any agent using this server can exfiltrate or modify any file on the host.
Test history
1 runEvery evaluation behind the score. This is the receipt.
- PassmanualReliability
88/100
Latency5 ms
SetupEasy
Flags1
All 13 advertised tools verified functional: read_file, read_binary_file, read_multiple_files, write_file, edit_file, create_directory, list_directory, directory_tree, move_file, search_files, get_file_info, list_directory_info, get_pwd. Reads, writes, listing, and search all return correct results. The server is functionally complete as advertised. The 'unrestricted' descriptor in the npm description is accurate and intentional.
HighUNRESTRICTED_FILESYSTEM_ACCESS
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