This indicates an attack attempt against an Arbitrary File Download vulnerability in Joomla! component JoomlaWorks AllVideos.
The vulnerability is due to insufficient sanitizing of user supplied inputs when handling a crafted HTTP request. An unauthenticated remote attacker can exploit this to download backup files that results in disclosure of information which could be used to further compromise the targeted system.
Joomla! component JoomlaWorks AllVideos version 3.0 to version 3.2
Information Disclosure: Remote attackers can gain sensitive information from vulnerable systems.
Applied patch or upgrade to the latest version from the vendor.