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TI-2026-68418 Aliases CVE-2026-105789

Arbitrary file write in Microsoft UFO Linux MCP execute_command tool

Priority LOW 26CWE-184Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Required
Attack complexity
High
Impact type
Code execution
Confidentiality · integrity · availability
None · High · Low
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-88.

Summary

Microsoft UFO versions before 3.0.9 are affected. The execute_command tool in the Linux MCP server treats sort and uniq as read-only commands, but their file-output forms are reachable through the free-form command parameter, which is an argument injection flaw (CWE-88). An authenticated caller can create or overwrite files writable by the UFO server process, which can corrupt configuration or disrupt the service, but the flaw does not directly disclose files or establish code execution.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

Microsoft UFO is an open-source framework for intelligent automation across devices and platforms. Prior to 3.0.9, the execute_command tool in ufo/client/mcp/http_servers/linux_mcp_server.py treats sort and uniq as read-only commands while the free-form command parameter can select their file-output forms. An authenticated caller can use sort -o or the optional second uniq operand to create or overwrite files writable by the UFO server process without shell metacharacters, because the allowed binary opens the destination itself and the argument policy does not reject the operation. This can corrupt configuration or other writable data and disrupt the service, but the demonstrated primitive does not directly disclose files or establish arbitrary code execution. This issue is fixed in version 3.0.9.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.007 53rd percentileScored 2026-11-07
Fix Fixed UFO (microsoft): 3.0.9

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftUFObefore 3.0.93.0.9Patch availableCNA
  • UFO VendorMicrosoft Affected before 3.0.9 Fixed in 3.0.9 Patch available CNA

Remediation

Update Microsoft UFO to version 3.0.9, which fixes this issue. The sources list no advisory identifier for the fix.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · CNA UFO (microsoft) Fixed in 3.0.9

Timeline

  1. 2026-10-06 Threatist record created from CVE-2026-105789

References

Other 4

  • TI-2026-42212 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-37256 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-26194 Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-16982 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2025-36863 Windows Server Update Service (WSUS) Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2025-33671 Microsoft SharePoint Server Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
See all 18045 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences