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Last week, newly exploited SharePoint vulnerabilities took a lot of our attention. It is fair to assume that last Monday (July 21st), all exposed vulnerable SharePoint installs were exploited. Of course, there is nothing to prevent multiple exploitation of the same instance, and a lot of that certainly happened. But why exploit it yourself if you can just take advantage of backdoors left behind by prior exploits? A number of these backdoors were widely publicised. The initial backdoor "spinstall0.aspx", was frequently observed and Microsoft listed various variations of this filename [1].