Path Interception by Unquoted Path
Adversaries may execute their own malicious payloads by hijacking vulnerable file path references. Adversaries can take advantage of paths that lack surrounding quotations by placing an executable in a higher level directory within the path, so that Windows will choose the adversary's executable to launch.

Service paths (Citation: Microsoft CurrentControlSet Services) and shortcut paths may also be vulnerable to path interception if the path has one or more spaces and is not surrounded by quotation marks (e.g., <code>C:\unsafe path with space\program.exe</code> vs. <code>"C:\safe path with space\program.exe"</code>). (Citation: Help eliminate unquoted path) (stored in Windows Registry keys) An adversary can place an executable in a higher level directory of the path, and Windows will resolve that executable instead of the intended executable. For example, if the path in a shortcut is <code>C:\program files\myapp.exe</code>, an adversary may create a program at <code>C:\program.exe</code> that will be run instead of the intended program. (Citation: Windows Unquoted Services) (Citation: Windows Privilege Escalation Guide)

This technique can be used for persistence if executables are called on a regular basis, as well as privilege escalation if intercepted executables are started by a higher privileged process.
source_name: mitre-attack  url: https://attack.mitre.org/techniques/T1574/009  external_id: T1574.009     source_name: Windows Privilege Escalation Guide  description: absolomb. (2018, January 26). Windows Privilege Escalation Guide. Retrieved August 10, 2018.  url: https://www.absolomb.com/2018-01-26-Windows-Privilege-Escalation-Guide/     source_name: Windows Unquoted Services  description: HackHappy. (2018, April 23). Windows Privilege Escalation – Unquoted Services. Retrieved August 10, 2018.  url: https://securityboulevard.com/2018/04/windows-privilege-escalation-unquoted-services/     source_name: Help eliminate unquoted path  description: Mark Baggett. (2012, November 8). Help eliminate unquoted path vulnerabilities. Retrieved November 8, 2012.  url: https://isc.sans.edu/diary/Help+eliminate+unquoted+path+vulnerabilities/14464     source_name: Microsoft CurrentControlSet Services  description: Microsoft. (2017, April 20). HKLM\SYSTEM\CurrentControlSet\Services Registry Tree. Retrieved March 16, 2020.  url: https://docs.microsoft.com/en-us/windows-hardware/drivers/install/hklm-system-currentcontrolset-services-registry-tree     