Description
@sylphxltd/filesystem-mcp v0.5.8 is an MCP server that provides file content reading functionality. Version 0.5.8 of filesystem-mcp contains a critical path traversal vulnerability in its "read_content" tool. This vulnerability arises from improper symlink handling in the path validation mechanism: the resolvePath function checks path validity before resolving symlinks, while fs.readFile resolves symlinks automatically during file access. This allows attackers to bypass directory restrictions by leveraging symlinks within the allowed directory that point to external files, enabling unauthorized access to files outside the intended operational scope.
Affected products
sylphx: filesystem mcp
References2
- github.com/sylphxltd/filesystem-mcp/issues/134 ExploitThird Party Advisory
- github.com/sylphxltd/filesystem-mcp Product
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 1% percentile: 51 · as of 11 November 2026
- CWE
- CWE-23
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