/usr/share/z-push/backend/ is in z-push-backend-kopano 2.3.8-2ubuntu1.
This file is owned by root:root, with mode 0o755.
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/usr/share/z-push/backend/kopano/
/usr/share/z-push/backend/kopano/config.php
/usr/share/z-push/backend/kopano/exporter.php
/usr/share/z-push/backend/kopano/icalparser.php
/usr/share/z-push/backend/kopano/importer.php
/usr/share/z-push/backend/kopano/kopano.php
/usr/share/z-push/backend/kopano/kopanochangeswrapper.php
/usr/share/z-push/backend/kopano/listfolders.php
/usr/share/z-push/backend/kopano/mapi/
/usr/share/z-push/backend/kopano/mapi/class.baseexception.php
/usr/share/z-push/backend/kopano/mapi/class.baserecurrence.php
/usr/share/z-push/backend/kopano/mapi/class.freebusypublish.php
/usr/share/z-push/backend/kopano/mapi/class.mapiexception.php
/usr/share/z-push/backend/kopano/mapi/class.meetingrequest.php
/usr/share/z-push/backend/kopano/mapi/class.recurrence.php
/usr/share/z-push/backend/kopano/mapi/class.taskrecurrence.php
/usr/share/z-push/backend/kopano/mapi/class.taskrequest.php
/usr/share/z-push/backend/kopano/mapi/mapi.util.php
/usr/share/z-push/backend/kopano/mapi/mapicode.php
/usr/share/z-push/backend/kopano/mapi/mapidefs.php
/usr/share/z-push/backend/kopano/mapi/mapiguid.php
/usr/share/z-push/backend/kopano/mapi/mapitags.php
/usr/share/z-push/backend/kopano/mapimapping.php
/usr/share/z-push/backend/kopano/mapiphpwrapper.php
/usr/share/z-push/backend/kopano/mapiprovider.php
/usr/share/z-push/backend/kopano/mapistreamwrapper.php
/usr/share/z-push/backend/kopano/mapiutils.php
/usr/share/z-push/backend/kopano/replybackimexporter.php
/usr/share/z-push/backend/kopano/replybackstate.php
/usr/share/z-push/backend/kopano/tnefparser.php