In case there are warnings that aren't related to permission issues that show up, instead of disabling warnings, you could stash any warnings File::Find throws into an array, and quickly grep through them for lines not matching any expected warnings to ensure nothing bad is happening in the background without being notified:

use warnings;
use strict;

use File::Find;

my @warnings;
{
    local $SIG{__WARN__} = sub {push @warnings, shift;};
    find ({wanted => \&wanted}, '.');
}

warn "this warning outside of File::Find, so will print normally\n";

sub wanted {
    # do stuff
}

print "caught: $_\n" for @warnings;

__END__
this warning outside of File::Find, so will print normally
caught: Can't cd to (./) test: Permission denied
 at find.pl line 10.
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