Allow Only Safe File Types to Be Uploaded
Limits uploads to common images, documents, audio and video, and rejects files with a hidden second extension such as photo.php.jpg.
Snippet Library
Security snippets for WordPress
Snippets that harden WordPress: turn off XML-RPC, hide the version number, stop user enumeration, add security headers and block risky uploads. Small, reviewable changes for site owners who want fewer attack points without a heavy security plugin.