Privileged windows installer

For example, you can enable the BlockNonAdminUserInstall policy to prevent non-administrator users from installing any Windows Appx applications. You can also enable the AllowAllTrustedAppToInstall policy to prevent users from installing programs from outside the store, that is, you can only install from the Microsoft Store if you want to install it. Of course, the easiest way is to install the latest cumulative update directly.

NinjaRMM Agents prior to version 5. Default permissions of both the directory and the executable file grants non-administrative users write access. This type of vulnerability, how to exploit and mitigate it is also described in the following resources:. The Windows Installer can be executed with msiexec. During execution, SysInternals Process Monitor was used to monitor actions of the process.

It was identified that an. Inspecting permissions of the directory and executable reveals that it is indeed unprotected our non-administrative user has Full control :. Since the non-administrative user has write permission to the directory and file, we can exploit the race condition by placing our own executable file or symbolic link before the installer, lock the file for writing, and wait for the installer to execute the file. However, in what's a case of an insufficient patch, Naceri found that it was not only possible to bypass the fix implemented by Microsoft but also achieve local privilege escalation via a newly discovered zero-day bug.

An attacker with admin privileges could then abuse the access to gain full control over the compromised system, including the ability to download additional software, and modify, delete, or exfiltrate sensitive information stored in the machine.

Tested on Windows 10 20H2 and Windows The Privileged property indicates whether the installation is performed in the context of elevated privileges. The installer sets this property if the user has administrator privileges, if the application has been assigned by a system administrator, or if both the user and machine policies AlwaysInstallElevated are set to true.

The installer does not set this property if the user is not allowed to install with elevated privileges. Developers of installer packages can use the Privileged property to make the installation conditional upon system policy, the user being an administrator, or assignment by an administrator.