BoldGrid W3 Total Cache vulnerabilities

The W3 Total Cache plugin for WordPress is vulnerable to Directory Traversal in all versions up to, and including, 2.9.4 via the setupSources function. This makes it possible for unauthenticated attackers to read the contents of arbitrary files on the server, which can contain sensitive information. Exploitation requires enabling manual minify mode and supplying a manual-format minify filename so that the hash is empty and the f_array[] entries are not overwritten before reaching setupSources().

The W3 Total Cache plugin for WordPress is vulnerable to information exposure in all versions up to, and including, 2.9.3. This is due to the plugin bypassing its entire output buffering and processing pipeline when the request's User-Agent header contains "W3 Total Cache", which causes raw mfunc/mclude dynamic fragment HTML comments — including the W3TC_DYNAMIC_SECURITY security token — to be rendered in the page source. This makes it possible for unauthenticated attackers to discover the value of the W3TC_DYNAMIC_SECURITY constant by sending a crafted User-Agent header to any page that contains developer-placed dynamic fragment tags, granted the site has the fragment caching feature enabled. With the leaked W3TC_DYNAMIC_SECURITY token, an attacker can craft valid mfunc tags to execute arbitrary PHP code on the server, achieving remote code execution.