PageAttachment is a MediaWiki extension to allow adding files to a wiki page as attachments.
By default, attachments are only allowed to be added to pages in the "Main" namespace (For more details on namespace, see MediaWiki's Help Page on Namespaces). Through configuration changes, attachments can be allowed to be attached to any other pages under other namespaces, for example, "User Talk" pages. See the Configuration section for all the available configuration options.
This extension adds an attachment list box on the wiki page with buttons that allow you to add, remove attachments and other functions. See the screenshot below: