Yes, see eval but this is not the best way to build XML.

#!/usr/bin/perl
use strict;
use XML::Simple 'XMLout'; 
  
my $samstr = 'source=>[
   { abc => [
     { uname =>["USER"],
       dbcrdn=>["PWD"],
       paridn=>["XYZ"],
       osath =>["0"],
     }]  }]';
 
my $xmlstr;
eval '$xmlstr = {'.$samstr.'}'; 
print XMLout($xmlstr,RootName => "root");
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