/usr/share/z-push/ is in z-push-backend-imap 2.3.8-2ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/z-push/backend/
/usr/share/z-push/backend/imap/
/usr/share/z-push/backend/imap/Auth/
/usr/share/z-push/backend/imap/Auth/SASL/
/usr/share/z-push/backend/imap/Auth/SASL.php
/usr/share/z-push/backend/imap/Auth/SASL/Anonymous.php
/usr/share/z-push/backend/imap/Auth/SASL/Common.php
/usr/share/z-push/backend/imap/Auth/SASL/CramMD5.php
/usr/share/z-push/backend/imap/Auth/SASL/DigestMD5.php
/usr/share/z-push/backend/imap/Auth/SASL/External.php
/usr/share/z-push/backend/imap/Auth/SASL/Login.php
/usr/share/z-push/backend/imap/Auth/SASL/Plain.php
/usr/share/z-push/backend/imap/Auth/SASL/SCRAM.php
/usr/share/z-push/backend/imap/Mail/
/usr/share/z-push/backend/imap/Mail.php
/usr/share/z-push/backend/imap/Mail/mail.php
/usr/share/z-push/backend/imap/Mail/sendmail.php
/usr/share/z-push/backend/imap/Mail/smtp.php
/usr/share/z-push/backend/imap/Net/
/usr/share/z-push/backend/imap/Net/SMTP.php
/usr/share/z-push/backend/imap/Net/Socket.php
/usr/share/z-push/backend/imap/README
/usr/share/z-push/backend/imap/REQUIREMENTS
/usr/share/z-push/backend/imap/THANKS
/usr/share/z-push/backend/imap/config.php
/usr/share/z-push/backend/imap/imap.php
/usr/share/z-push/backend/imap/mimePart.php
/usr/share/z-push/backend/imap/mime_calendar.php
/usr/share/z-push/backend/imap/mime_encode.php
/usr/share/z-push/backend/imap/user_identity.php