If it's just a hash and all you're looking for is a copy of it:
my $hashref = {data => "a"};
my %hash_copy = %{$hashref}; # Create a copy of the hash that $hashref points to
my $hashref_copy = \%hash_copy; # Ref to %hash_copy
$hashref_copy->{data} = "b";
print "$hashref->{data}\n"; # Outputs 'a'
print "$hashref_copy->{data}\n"; # Outputs 'b'
