Warning: require(/var/www/wordpress/wp-includes/version.php): Failed to open stream: Permission denied in /var/www/wordpress/wp-settings.php on line 33

Fatal error: Uncaught Error: Failed opening required '/var/www/wordpress/wp-includes/version.php' (include_path='.:/usr/local/lib/php') in /var/www/wordpress/wp-settings.php:33 Stack trace: #0 /var/www/wordpress/wp-config.php(145): require_once() #1 /var/www/wordpress/wp-load.php(50): require_once('/var/www/wordpr...') #2 /var/www/wordpress/wp-blog-header.php(13): require_once('/var/www/wordpr...') #3 /var/www/wordpress/index.php(17): require('/var/www/wordpr...') #4 {main} thrown in /var/www/wordpress/wp-settings.php on line 33