T1574.009 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 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.,
C:\unsafe path with space\program.exe vs.
“C:\safe path with space\program.exe”). (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
C:\program files\myapp.exe, an adversary may create a program at
C:\program.exe that will be run instead of the intended program.
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.
||T1574.001, T1574.002, T1574.004, T1574.005, T1574.006, T1574.007, T1574.008, T1574.009, T1574.010, T1574.011, T1574.012, T1574.013
||TA0003, TA0004, TA0005
||13 March 2020
||30 March 2023
||Empire contains modules that can discover and exploit unquoted path vulnerabilities.
||PowerSploit contains a collection of Privesc-PowerUp modules that can discover and exploit unquoted path vulnerabilities.
||Find and eliminate path interception weaknesses in program configuration files, scripts, the PATH environment variable, services, and in shortcuts by surrounding PATH variables with quotation marks when functions allow for them. Be aware of the search order Windows uses for executing or loading binaries and use fully qualified paths wherever appropriate.
||Adversaries will likely need to place new binaries in locations to be executed through this weakness. Identify and block potentially malicious software executed path interception by using application control tools, like Windows Defender Application Control, AppLocker, or Software Restriction Policies where appropriate.
||Restrict File and Directory Permissions
||Ensure that proper permissions and directory access control are set to deny users the ability to write files to the top-level directory
C: and system directories, such as
C:\Windows\, to reduce places where malicious files could be placed for execution. Require that all executables be placed in write-protected directories.