CVE-2026-105791: CWE-88: Improper Neutralization of Argument Delimiters in a Command ('Argument Injection') in microsoft UFO
Description
CVE-2026-105791 is a high-severity vulnerability in Microsoft UFO, an open-source automation framework. Versions prior to 3.0.9 have an improper neutralization of argument delimiters in the run_shell tool of the CommandLineExecutor component. This flaw allows an attacker to execute arbitrary code by exploiting how explorer.exe delegates path arguments to ShellExecute on Windows, despite the subprocess using shell=False. Successful exploitation requires user interaction to run an affected workflow and invoke the vulnerable tool call. The vulnerability is fixed in version 3.0.9.
CVSS v3.1
Score 7.5high
Affected software
microsoft
UFO
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Microsoft UFO versions before 3.0.9 contain an argument injection vulnerability (CWE-88) in the run_shell tool within the CommandLineExecutor component. The tool only validates the first token of the bash_command parameter and permits explorer.exe. On Windows, explorer.exe passes its subsequent path argument to ShellExecute, enabling an attacker-controlled agent call to launch arbitrary executables or scripts as the desktop user. This occurs even though the subprocess is invoked with shell=False. Exploitation requires a user to run an affected agent workflow and trigger the vulnerable call. The issue is resolved in version 3.0.9.
Potential Impact
Exploitation can lead to arbitrary code execution with the privileges of the desktop user running the affected workflow. This allows an attacker to access or modify the user's files, tokens, and sessions, potentially leading to full compromise of the user's environment. The attack requires user interaction and the execution of a crafted workflow that triggers the vulnerability.
Mitigation Recommendations
Upgrade Microsoft UFO to version 3.0.9 or later, where this vulnerability is fixed. No other mitigations are specified. Users should ensure they do not run workflows with untrusted input on affected versions.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-10-05T20:37:19.363Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6ac506e32cdf04f656b9a05b
Added to database: 10/06/2026, 14:34:11 UTC
Last enriched: 10/06/2026, 14:48:42 UTC
Last updated: 10/06/2026, 18:57:28 UTC
Views: 14
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