Those directories hold the installed Perl system and should be 0755 for directories and 0644 for files. I believe that chown a+rX -R `perl -e 'print(join("\n", @INC))'` at a root prompt should fix it. The root cause was probably a bad umask value while updating Perl modules.

Those permissions are not overblown at all — most of the system should be accessible to all users.