Akeeba Backup, versions 5.5.1 and previous, various issues (see developer's site for details: https://www.akeebabackup.com/news/1686-security-updates-august-2017.html)
Resolution: update to 5.5.2
Update notice: https://www.akeebabackup.com/component/ars/?view=Items&release_id=2732
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