/usr/share/perl5/ is in libauthen-sasl-perl 2.1600-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/perl5/Authen/
/usr/share/perl5/Authen/SASL/
/usr/share/perl5/Authen/SASL/EXTERNAL.pm
/usr/share/perl5/Authen/SASL/Perl.pod
/usr/share/perl5/Authen/SASL/CRAM_MD5.pm
/usr/share/perl5/Authen/SASL/Perl.pm
/usr/share/perl5/Authen/SASL/Perl/
/usr/share/perl5/Authen/SASL/Perl/PLAIN.pm
/usr/share/perl5/Authen/SASL/Perl/EXTERNAL.pm
/usr/share/perl5/Authen/SASL/Perl/LOGIN.pm
/usr/share/perl5/Authen/SASL/Perl/DIGEST_MD5.pm
/usr/share/perl5/Authen/SASL/Perl/ANONYMOUS.pm
/usr/share/perl5/Authen/SASL/Perl/CRAM_MD5.pm
/usr/share/perl5/Authen/SASL/Perl/GSSAPI.pm
/usr/share/perl5/Authen/SASL.pm
/usr/share/perl5/Authen/SASL.pod