SVG uploads in WordPress (the Inconvenient Truth)

Enabling uploads of SVG files in WordPress is quite easy, and there is a tonne of posts on the Interwebs explaining how you do it. Usually along the lines of:

function add_svg_to_upload_mimes( $upload_mimes ) { 
	$upload_mimes['svg'] = 'image/svg+xml'; 
	$upload_mimes['svgz'] = 'image/svg+xml'; 
	return $upload_mimes; 
} 
add_filter( 'upload_mimes', 'add_svg_to_upload_mimes', 10, 1 );

And that’s pretty much it.

Except it is not.

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Run all due cron events for WordPress with WP-CLI

Running a real cronjob is much more reliable than WordPress’ built-in “maybe-will-trigger” solution. But if you’re running a multisite network, you have to add a crontab entry for every site you set up – which is tedious. Thanks to WP-CLI, we can use a small bash script instead, which will run all due events for all sites for us. Oh, and it works for single sites as well.Continue reading “Run all due cron events for WordPress with WP-CLI”

How to upgrade to PHP 7 on Ubuntu

Depending on your time zone, PHP 7 was finally released on 3rd/4th of December 2015. Even though the general recommendation for production servers is to wait for a little bit and gather some experiences before upgrading, some of us want to jump right on and upgrade to PHP 7.

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Restrict allowed HTTP methods in Nginx

Security vulnerabilities are often exploits of software that fails when trying to deal with unexpected input. Other times they are exploits of a misconfiguration or a service that unintentionally was open to the public.

For the above reasons, we should limit as much as possible what services are exposed to the public and limit as much as possible what they do and accept from the visitors. To follow those security principles, we should only allow the HTTP methods for which we, in fact, provide services. Under all normal circumstances, that would be the methods GET, POST and HEAD.

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Block access to PHP files on your WordPress site with Nginx

In your WordPress site, there are directories that include PHP files that visitors should never be able to access directly. They are only there for WordPress to function as an application that runs on your server. But because of WordPress’ directory and file structure, they are kind of accessible to the public. All of them are meant to be part of a larger application – WordPress, that is – and should not cause any harm if called directly – that we know. Some of the files execute some code even when ran standalone. An attacker might know of a clever way to make that code run in an unexpected manner, causing harm. To be on the safe side, we should deny access to all these PHP files from the outside world. Since we block access to them in our Nginx configuration, PHP will still run them as usual and WordPress will work just fine.

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Restrict access to the WordPress dashboard by IP address in Nginx

If you have a static IP address, like from your office, or your own private VPN, you can increase your security tremendously by restricting all logins to that IP address. The effect is that even if an attacker knows your login credentials, they will not be able to log in or access any part of the WordPress Dashboard.

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Redirect all HTTP requests to HTTPS with Nginx

All login credentials transferred over plain HTTP can easily be sniffed by an MITM attacker, but is is not enough to encrypt the login forms. If you are visiting plain HTTP pages while logged in, your session can be hijacked, and not even two-factor authentication will protect you. To protect all info sent between your visitors – which includes you – and your web server, we will redirect all requests that are coming over plain HTTP to the HTTPS equivalent.

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Strict file ownership for your WordPress installation

WordPress requires write access to one directory, and that one directory only: the directory returned by wp_upload_dir(). By default, this is /wp-content/upload, but it can be configured to anything that is beneath your document root, like /media, if you want to.

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