CVE-2026-85661
excel-mcp-server 0.1.8 fails to enforce path confinement in stdio mode when EXCEL_FILES_PATH is unset, allowing attackers to read and write arbitrary files. Attackers can supply unchecked file paths to read and write tools to access any file accessible to the process.
Weakness
excel-mcp-server 0.1.8 fails to enforce path confinement in stdio mode when EXCEL_FILES_PATH is unset, allowing attackers to read and write arbitrary files. Attackers can supply unchecked file paths to read and write tools to access any file accessible to the process.
References
- https://github.com/haris-musa/excel-mcp-server
- https://github.com/haris-musa/excel-mcp-server/blob/v0.1.8/src/excel_mcp/server.py
- https://github.com/haris-musa/excel-mcp-server/blob/v0.1.8/src/excel_mcp/validation.py
- https://github.com/haris-musa/excel-mcp-server/issues/149
- https://www.vulncheck.com/advisories/excel-mcp-server-0.1.8-arbitrary-file-read-write-via-stdio-mode
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