PHP Configuration Cheat Sheet¶
This page is meant to help those configuring PHP and the web server it is running on to be very secure.
Below you will find information on the proper settings for the
php.ini file and instructions on configuring Apache, Nginx, and Caddy web servers.
For general PHP codebase security please refer to the two following great guides:
PHP Configuration and Deployment¶
Some of following settings need to be adapted to your system, in particular
You should also be running PHP 7.2 or later. If running PHP 7.0 and 7.1, you will use slightly different values in a couple of places below (see inline comments). Finally look through the PHP Manual for a complete reference on every value in the php.ini configuration file.
You can find a copy of the following values in a ready-to-go php.ini file here.
PHP error handling¶
expose_php = Off error_reporting = E_ALL display_errors = Off display_startup_errors = Off log_errors = On error_log = /valid_path/PHP-logs/php_error.log ignore_repeated_errors = Off
Keep in mind that you need to have
Off on a production server and it's a good idea to frequently notice the logs.
PHP general settings¶
doc_root = /path/DocumentRoot/PHP-scripts/ open_basedir = /path/DocumentRoot/PHP-scripts/ include_path = /path/PHP-pear/ extension_dir = /path/PHP-extensions/ mime_magic.magicfile = /path/PHP-magic.mime allow_url_fopen = Off allow_url_include = Off variables_order = "GPCS" allow_webdav_methods = Off session.gc_maxlifetime = 600
allow_url_* prevents LFIs to be easily escalated to RFIs.
PHP file upload handling¶
file_uploads = On upload_tmp_dir = /path/PHP-uploads/ upload_max_filesize = 2M max_file_uploads = 2
If your application is not using file uploads, and say the only data the user will enter / upload is forms that do not require any document attachments,
file_uploads should be turned
PHP executable handling¶
enable_dl = Off disable_functions = system, exec, shell_exec, passthru, phpinfo, show_source, highlight_file, popen, proc_open, fopen_with_path, dbmopen, dbase_open, putenv, move_uploaded_file, chdir, mkdir, rmdir, chmod, rename, filepro, filepro_rowcount, filepro_retrieve, posix_mkfifo # see also: http://ir.php.net/features.safe-mode disable_classes =
These are dangerous PHP functions. You should disable all that you don't use.
PHP session handling¶
Session settings are some of the MOST important values to concentrate on in configuring. It is a good practice to change
session.name to something new.
session.save_path = /path/PHP-session/ session.name = myPHPSESSID session.auto_start = Off session.use_trans_sid = 0 session.cookie_domain = full.qualified.domain.name #session.cookie_path = /application/path/ session.use_strict_mode = 1 session.use_cookies = 1 session.use_only_cookies = 1 session.cookie_lifetime = 14400 # 4 hours session.cookie_secure = 1 session.cookie_httponly = 1 session.cookie_samesite = Strict session.cache_expire = 30 session.sid_length = 256 session.sid_bits_per_character = 6 # PHP 7.2+ session.hash_function = 1 # PHP 7.0-7.1 session.hash_bits_per_character = 6 # PHP 7.0-7.1
Some more security paranoid checks¶
session.referer_check = /application/path memory_limit = 50M post_max_size = 20M max_execution_time = 60 report_memleaks = On track_errors = Off html_errors = Off
Suhosin is a patch to PHP which provides a number of hardening and security features that are not available in the default PHP build. However, Suhosin only works with PHP 5, which is unsupported and should not be used.
For PHP 7, there is Suhosin-ng, but it's in a prerelease stage, and as such should not be used in production.
Snuffleupagus is the spiritual descendent of Suhosin for PHP 7 and onwards, with modern features. It's considered stable, and is usable in production.