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CVE

CVE-2026-85661

excel-mcp-server 0.1.8 Arbitrary File Read/Write via stdio mode
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CVE

CVE-2026-85661

excel-mcp-server 0.1.8 Arbitrary File Read/Write via stdio mode

excel-mcp-server 0.1.8 fails to enforce path confinement in stdio mode when EXCELFILESPATH 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.

Package Versions Affected

Package Version
patch Availability
No items found.

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CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
9.3
-
4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
C
H
U
0
-
C
H
U
-

Related Resources

No items found.

References

https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/85xxx/CVE-2026-85661.json, https://nvd.nist.gov/vuln/detail/CVE-2026-85661, https://www.vulncheck.com/advisories/excel-mcp-server-0.1.8-arbitrary-file-read-write-via-stdio-mode, https://github.com/haris-musa/excel-mcp-server/issues/149, https://github.com/haris-musa/excel-mcp-server, https://github.com/haris-musa/excel-mcp-server/blob/v0.1.8/src/excelmcp/server.py, https://github.com/haris-musa/excel-mcp-server/blob/v0.1.8/src/excelmcp/validation.py

Severity

0

CVSS Score
0
10

Basic Information

Base CVSS
0
EPSS Probability
0.00687%
EPSS Percentile
0.51194%
Introduced Version
0
Fix Available

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