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 Metasploit module has been tested against Windows 10 Pro x64.

CVE-2018-8440