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Security Checklist/Hosting and Server Setup

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Revision as of 11:22, 28 January 2010 by Knightofmathematics (Talk | contribs)

Contents

Choose a Qualified Hosting Provider

The most important decision

Probably no decision is more critical to site security than the choice of hosts and servers. However, due to the wide variety of hosting options and configurations, it's not possible to provide a complete list for all situations. Check this unbiased list of recommended hostswho fully meet the security requirements of a typical Joomla site. (FAQ)

Shared server risks

If you are on a tight budget and your site does not process highly confidential data, you can probably get by with a shared server, but you must understand the unavoidable risks. Most of the tips listed below are appropriate for securing sites on shared server environments.

Avoid sloppy server configurations

For a real eye-opener, read this report on thousands of sites that allowed Google to index the results of phpinfo(). Don't make this mistake on your site! The report includes alarming statistics on the percentage of sites that use depreciated settings such as register_globals ON or that don't have open_basedir set at all: By the way, if phpini and register_globals are unfamiliar terms you are probably not ready to securely manage your own site.

Configuring Apache

Use Apache .htaccess

See also .htaccess examples

Block typical exploit attempts with local Apache .htaccess files. This option is not enabled on all servers. Check with your host if you run into problems. Using .htaccess, you can password protect sensitive directories, such as administrator, restrict access to sensitive directories by IP Address, and depending on your server's configuration, you may be able to increase security by switching from PHP4 to PHP5.
Joomla ships with a preconfigured .htaccess file, but *you* need to choose to use it. The file is called htaccess.txt; to use it rename it to .htaccess and place it in the root of your webpage.
Consider following the "Least Privilege" principle for running PHP using tools such as PHPsuExec, php_suexec or suPHP. (Note: These are advanced methods that require agreement and coordination with your hosting provider. Such options are enabled or disabled on a server-wide basis and are not individually adjustable on shared servers.)

Use Apache mod_security

Configure Apache mod_security and mod_rewrite filters to block PHP attacks. See Google search for mod_security and Google search for mod_rewrite. (Note: These are advanced methods that usually require agreement and coordination with your hosting provider. Such options are enabled or disabled on a server-wide basis and are not individually adjustable on shared servers.)

Configuring MySQL

Secure the database

Be sure MySQL accounts are set with limited access. The initial install of MySQL is insecure and careful configuration is required. (See the MySQL Manuals) Note: This item applies only to those administering their own servers, such as dedicated servers. Users of shared servers are dependent on their hosting provider to set proper database security.)

Configuring PHP

Understand how PHP works

Understand how to work with the php.ini file, and how PHP configurations are controlled. Study the Official List of php.ini Directives at http://www.php.net, and the well-documented default php.ini file included with every PHP install. Here is the latest default php.ini file on the official PHP site.

Use PHP5

Currently, both PHP4 and PHP5 are maintained, and both are often available on servers. Before PHP4 becomes obsolete, upgrade your custom scripts to PHP5. Don't worry about core Joomla code; all current versions are PHP5 compatible. (See PHP News)

Use local php.ini files

On shared servers you can't edit the main php.ini file, but you may be able to add custom, local php.ini files. If so, you'll need to copy the php.ini files to every sub-directory that requires custom settings. Luckily a set of scripts at B & T Scripts and Tips can do the hard work for you.
There are a few important things to keep in mind.
  1. Local php.ini files only have an effect if your server is configured to use them. This includes a php.ini file in your http_root directory. You can test whether or not these file affect your site by setting an obvious directive in the local php.ini file to see if it affects your site.
  2. Local php.ini files only effect .php files that are located within the same directory (or included() or required() from those files). This means that there are normally only two Joomla! directories in which you would want to place a php.ini file. They are your http_root(your actual directory name may vary), which is where Joomla's Front-end index.php file is located, and the Joomla! administrator directory, which is where the Back-end administrator index.php file is located. Other directories that don't have files called via the Web do not need local php.ini files.
  3. If you have a php.ini file in every directory, some script probably did this for you. If you didn't intend it to happen, you probably should root them out, but given #2 above, you probably only have to panic about the php.ini files in http_root and the administrator directories.

Use PHP disable_functions

Use disable_functions to disable dangerous PHP functions that are not needed by your site. Here is a typical setup for a Joomla! site:
     disable_functions = show_source, system, shell_exec, passthru, exec, phpinfo, popen, proc_open

Use PHP open_basedir

open_basedir should be enabled and correctly configured. This directive limits the files that can be opened by PHP to the specified directory-tree. This directive is NOT affected by whether Safe Mode is ON or OFF.
The restriction specified with open_basedir is a prefix, not a directory name. This means that open_basedir = /dir/incl allows access to /dir/include and /dir/incls if they exist. To restrict access to only the specified directory, end with a slash. For more information, see PHP Security and Safe Mode Configuration Directives.
    open_basedir = /home/users/you/public_html
In some system configurations, at least with PHP 4.4.8, the use of the trailing slash to restrict the access to only the specified directory may cause Joomla to warn JFolder::create: Infinite loop detected when saving the Back-End Global Configuration. This warning is triggered because PHP file_exists() function fails, for example, when asked if /home/user/public_html/joomla_demo exists and open_basedir is set to /home/user/public_html/joomla_demo/ (see the trailing slash).
Additionally, if open_basedir is set it may be necessary to set PHP upload_tmp_dir configuration directive to a path that falls within the scope of open_basedir or, alternatevely, add the upload_tmp_dir path to open_basedir using the appropriate path separator for the host system.
    open_basedir = /home/users/you/public_html:/tmp
PHP will use the system's temporary directory when upload_tmp_dir is not set or when it is set but the directory does not exist, therefore it may be necessary to add it to open_basedir as above to avoid uploading errors within Joomla.

Adjust magic_quotes_gpc

Adjust the magic_quotes_gpc directive as needed for your site. The recommended setting for Joomla! 1.0.x is ON to protect against poorly-written third-party extensions. The safest method is to turn magic_quotes_gpc off and avoid all poorly-written extensions, period.
Joomla! 1.5 ignores this setting and works fine either way. For more information, see PHP Manual, Chapter 31. Magic Quotes.
     magic_quotes_gpc = 1

Don't use PHP safe_mode

Avoid the use of PHP safe_mode. This is a valid but incomplete solution to a deeper problem and provides a false sense of security. See the official PHP site for an explanation of this issue.
     safe_mode = 0

Don't use PHP register_globals

Automatically registering global variables was probably one of the dumbest decisions the developers of PHP made. This directive determines whether or not to register the EGPCS (Environment, GET, POST, Cookie, Server) variables as global variables where they become immediately available to all PHP scripts, and where they can easily overwrite your own variable if you're not careful. Luckily, the PHP developers long since realized the mistake and have depreciated this 'feature'.
If your site is on a shared server with a hosting provider that insists register_globals must be on, you should be very worried. Although you can often turn register_globals off for your own site with a local php.ini file, this adds little security as other sites on the same server remain vulnerable to attacks which can then launch attacks against your site from within the server. For more information, see ZEND Chapter 29. Using Register Globals.
     register_globals = 0

Don't use PHP allow_url_fopen

Don't use PHP allow_url_fopen. This option enables the URL-aware fopen wrappers that enable accessing URL object like files. Default wrappers are provided for the access of remote files using the ftp or http protocol, some extensions like zlib may register additional wrappers. Note: This can only be set in php.ini due to security reasons.
     allow_url_fopen = 0

Setup a backup and recovery process

The most important rule:'

Thou shalt at all time be able to return your site to a previous working state through regular use of a strong, off-site backup and recovery process. Be sure your backup and recovery process is in place and tested BEFORE you go live. This is the single best way (and often the only way) to recover from such inevitable catastrophes as:
  1. A compromised/cracked site.
  2. Broken site due to a faulty upgrade.
  3. Hardware failure, such as dead hard drives, power failures, server theft, etc.
  4. Authoritarian government intervention. (More common than some think.)
  5. Needing to quickly relocate to a new server or hosting provider.


Choose A Checklist

  1. Getting Started
  2. Hosting and Server Setup
  3. Testing and Development
  4. Joomla Setup
  5. Site Administration
  6. Site Recovery