Microsoft Windows ALPC Task Scheduler Local Privilege Elevation
Description
On vulnerable versions of Windows the alpc endpoint method SchRpcSetSecurity implemented by the task scheduler service can be used to write arbitrary DACLs to `.job` files located in `c:\windows\tasks` because the scheduler does not use impersonation when checking this location. Since users can create files in the `c:\windows\tasks` folder, a hardlink can be created to a file the user has read access to. After creating a hardlink, the vulnerability can be triggered to set the DACL on the linked file. WARNING: The PrintConfig.dll (%windir%\system32\driverstor\filerepository\prnms003*) on the target host will be overwritten when the exploit runs. This module has been tested against Windows 10 Pro x64.
Author(s)
- SandboxEscaper
- bwatters-r7
- asoto-r7
- Jacob Robles
Platform
Windows
Development
Module Options
To display the available options, load the module within the Metasploit console and run the commands 'show options' or 'show advanced':
msf > use exploit/windows/local/alpc_taskscheduler
msf exploit(alpc_taskscheduler) > show targets
...targets...
msf exploit(alpc_taskscheduler) > set TARGET < target-id >
msf exploit(alpc_taskscheduler) > show options
...show and set options...
msf exploit(alpc_taskscheduler) > exploit
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