When installing or uninstalling Exchange Cumulative Update (CU) installation may simply crash.
If you find "Could not load file or assembly 'Microsoft.Exchange.CabUtility.dll' in ExchangeSetup.log”, make sure that you have correct Visual C++ Redistributable Package for Visual Studio installed on your Exchange server. Check Exchange installation prerequisites.
Full error in the ExchangeSetup.log is:
[03.01.2019 20:36:20.0990]  [ERROR] Exception has been thrown by the target of an invocation.
[03.01.2019 20:36:21.0006]  [ERROR] Could not load file or assembly 'Microsoft.Exchange.CabUtility.dll' or one of its dependencies. The specified module could not be found.
[03.01.2019 20:36:21.0006]  Unable to load assembly from file C:\Program Files\Microsoft\Exchange Server\V15\bin\Microsoft.Exchange.Setup.GUI.dll using setup arguments /sourcedir:C:\Temp\Exchange2013CU22./mode:Install, source directory is C:\Temp\Exchange2013CU22, target directory is C:\Windows\Temp\ExchangeSetup and Exchange is installed True.