excel-mcp-server 0.1.8 Arbitrary File Read/Write via stdio mode
Priority MEDIUM 49CWE-22Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00687 52nd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| haris-musa | excel-mcp-server | up to 0.1.8 | — | No fix listed | CNA |
- excel-mcp-server Vendorharis-musa Affected up to 0.1.8 Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-85661
- 2026-10-03 Alias added: GHSA-xv88-r947-5c3v
References
More haris-musa vulnerabilities
- TI-2026-29316 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in excel-mcp-server CVSS 3.1CRITICAL 9.4
Sources
- CVE-2026-85661 · CVE Program
- CVE-2026-85661 · NVD
- FIRST EPSS
- GHSA-xv88-r947-5c3v · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences