The Classic Addons – WPBakery Page Builder plugin for WordPress is vulnerable to Limited Local PHP File Inclusion in all versions up to, and including, 3.0 via the 'style' parameter. This makes it possible for authenticated attackers, with Contributor-level access and above, and permissions granted by an Administrator, to include and execute arbitrary files on the server, allowing the execution of any PHP code in those files. This can be used to bypass access controls, obtain sensitive data, or achieve code execution in cases where images and other “safe” file types can be uploaded and included. The vulnerability is limited to PHP files in a Windows environment.
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.