/usr/share/perl5/Mail/ is in libmail-dkim-perl 0.39-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/perl5/Mail/DKIM/
/usr/share/perl5/Mail/DKIM.pm
/usr/share/perl5/Mail/DKIM/Algorithm/
/usr/share/perl5/Mail/DKIM/Algorithm/Base.pm
/usr/share/perl5/Mail/DKIM/Algorithm/dk_rsa_sha1.pm
/usr/share/perl5/Mail/DKIM/Algorithm/rsa_sha1.pm
/usr/share/perl5/Mail/DKIM/Algorithm/rsa_sha256.pm
/usr/share/perl5/Mail/DKIM/AuthorDomainPolicy.pm
/usr/share/perl5/Mail/DKIM/Canonicalization/
/usr/share/perl5/Mail/DKIM/Canonicalization/Base.pm
/usr/share/perl5/Mail/DKIM/Canonicalization/DkCommon.pm
/usr/share/perl5/Mail/DKIM/Canonicalization/DkimCommon.pm
/usr/share/perl5/Mail/DKIM/Canonicalization/dk_nofws.pm
/usr/share/perl5/Mail/DKIM/Canonicalization/dk_simple.pm
/usr/share/perl5/Mail/DKIM/Canonicalization/nowsp.pm
/usr/share/perl5/Mail/DKIM/Canonicalization/relaxed.pm
/usr/share/perl5/Mail/DKIM/Canonicalization/simple.pm
/usr/share/perl5/Mail/DKIM/Common.pm
/usr/share/perl5/Mail/DKIM/DNS.pm
/usr/share/perl5/Mail/DKIM/DkPolicy.pm
/usr/share/perl5/Mail/DKIM/DkSignature.pm
/usr/share/perl5/Mail/DKIM/DkimPolicy.pm
/usr/share/perl5/Mail/DKIM/Key.pm
/usr/share/perl5/Mail/DKIM/KeyValueList.pm
/usr/share/perl5/Mail/DKIM/MessageParser.pm
/usr/share/perl5/Mail/DKIM/Policy.pm
/usr/share/perl5/Mail/DKIM/PrivateKey.pm
/usr/share/perl5/Mail/DKIM/PublicKey.pm
/usr/share/perl5/Mail/DKIM/Signature.pm
/usr/share/perl5/Mail/DKIM/Signer.pm
/usr/share/perl5/Mail/DKIM/SignerPolicy.pm
/usr/share/perl5/Mail/DKIM/TextWrap.pm
/usr/share/perl5/Mail/DKIM/Verifier.pm
/usr/share/perl5/Mail/sample_mime_lite.pl