/usr/share/man/ is in exim4-config 4.89-2+deb9u3.
This file is owned by root:root, with mode 0o755.
..
/usr/share/man/man5/
/usr/share/man/man5/exim4-config_files.5.gz
/usr/share/man/man8/
/usr/share/man/man8/update-exim4.conf.8.gz
/usr/share/man/man8/update-exim4.conf.template.8.gz
/usr/share/man/man8/update-exim4defaults.8.gz
/usr/share/man/man5/etc-aliases.5.gz
/usr/share/man/man5/etc-email-addresses.5.gz
/usr/share/man/man5/exim4_exim_crt.5.gz
/usr/share/man/man5/exim4_exim_key.5.gz
/usr/share/man/man5/exim4_host_local_deny_exceptions.5.gz
/usr/share/man/man5/exim4_hubbed_hosts.5.gz
/usr/share/man/man5/exim4_local_domain_dnsbl_whitelist.5.gz
/usr/share/man/man5/exim4_local_host_blacklist.5.gz
/usr/share/man/man5/exim4_local_rcpt_callout.5.gz
/usr/share/man/man5/exim4_local_sender_blacklist.5.gz
/usr/share/man/man5/exim4_local_sender_callout.5.gz
/usr/share/man/man5/exim4_passwd.5.gz
/usr/share/man/man5/exim4_passwd_client.5.gz
/usr/share/man/man5/exim4_sender_local_deny_exceptions.5.gz
/usr/share/man/man5/update-exim4.conf.conf.5.gz