The Shared Files plugin for WordPress, which allows users to upload and share files securely, has a security vulnerability. This means that hackers can insert malicious code into the files, which will then run whenever someone tries to access them. This issue affects all versions of the plugin up to 1.7.42 and can be exploited by anyone, even without an account. However, it only affects websites that use Apache as their server and have not changed the default settings for handling dfxp files.