/usr/lib/ is in libcyrus-imap-perl 2.4.18-3.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/perl5/
/usr/lib/x86_64-linux-gnu/perl5/5.22/
/usr/lib/x86_64-linux-gnu/perl5/5.22/Cyrus/
/usr/lib/x86_64-linux-gnu/perl5/5.22/Cyrus/IMAP/
/usr/lib/x86_64-linux-gnu/perl5/5.22/Cyrus/IMAP/IMSP.pm
/usr/lib/x86_64-linux-gnu/perl5/5.22/Cyrus/IMAP/Shell.pm
/usr/lib/x86_64-linux-gnu/perl5/5.22/Cyrus/IMAP/Admin.pm
/usr/lib/x86_64-linux-gnu/perl5/5.22/Cyrus/IMAP.pm
/usr/lib/x86_64-linux-gnu/perl5/5.22/Cyrus/SIEVE/
/usr/lib/x86_64-linux-gnu/perl5/5.22/Cyrus/SIEVE/managesieve.pm
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Cyrus/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Cyrus/IMAP/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Cyrus/IMAP/IMAP.so
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Cyrus/SIEVE/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Cyrus/SIEVE/managesieve/
/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Cyrus/SIEVE/managesieve/managesieve.so