CVE-2026-85661
CRITICAL
NVD
CVSS Score
9.8
Severity
CRITICAL
Published
Sep 04, 2026
Vendor
unknown
Description
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