All vulnerabilities
CVE-2026-105789GHSA-85w2-wggf-rw49

Microsoft UFO: Arbitrary file write in the Linux MCP `execute_command` tool

microsoft UFO
CVSS
5.4Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.70%Chance of exploitation activity in the next 30 days, higher than 52% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed inNone listedNo source names a fixed version. Check the vendor advisory below
Published6 Oct 2026Updated 6 Oct 2026CVE List

What fixes it

No source in this snapshot names a fixed version. The vendor advisories under References are the place to check.

Description

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.

Text from CVE List

Affected versions 2

  • UFOaffected: < 3.0.9CVE List
  • microsoft/UFO, other<= 3.0.8GitHub

References 4