WordPress Core is vulnerable to Directory Traversal in versions up to, and including, 6.2, via the ‘wp_lang’ parameter. This allows unauthenticated attackers to access and load arbitrary translation files. In cases where an attacker is able to upload a crafted translation file onto the site, such as via an upload form, this could be also used to perform a Cross-Site Scripting attack.
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.