App hardening

Tested on: WordPress 6.5.x on Ubuntu 24.04 LTS, Nginx 1.26.x, PHP-FPM 8.3, MariaDB 10.11. Most settings translate directly to Apache; Nginx-specific blocks are clearly marked. Why this matters WordPress powers a large share of the web, which makes it the most attacked CMS. Most WordPress incidents are not novel — they are one of: An out-of-date plugin with a known CVE, exploited within days of public disclosure. wp-login.php brute-force, succeeding because an admin reused a password leaked from elsewhere. Filesystem permissions that let the web server write to source files, so a single PHP RCE becomes persistent. A backup containing the entire database, stored unencrypted, exposed via a misconfigured S3 bucket. For an agency hosting multiple client sites, the blast radius compounds: one compromised site can pivot to siblings via shared filesystem, shared database server, or shared PHP-FPM pool. This guide gives you a baseline that addresses each of the above and isolates per-site risk. ...