Nginx

Introduction This is a hardening profile to help securing nginx by using systemd unit configuration. It’s goal is to restrict what nginx can do and make it harder for any possible vulnerability to be misused. The rationale for the selected settings is based on the analysis as part of the article Hardening nginx with systemd security features.

Introduction Nginx is still a popular web server and powering a part of the web. Wouldn’t it be great if we could secure it a little bit more? In this article we use the security features to secure systemd units and services and apply it to nginx. If you are not familiar yet with the unit settings of systemd, then this document would be a good introduction into the subject.

Learn how to define the Expires header in nginx to improve the caching of static assets.

How to display the configured hosts by filtering out the server_name entries

Nginx is flexible when it comes to what should be logged in the access.log. With the combination of a map and if-statement, this can be achieved very easily!" Log only some events by HTTP status Creating a map using $status The $status variable contains the HTTP status code that is normally returned to each request. We can leverage this status code to set a so-called boolean (true/false, or 1/0). Let’s define first the map and use the HTTP status.

Gzip Gzip is well-known and around for some time. Almost all web clients support it and the savings are typically very high. Compressing a file with gzip is simple, especially with the command often already installed on Linux systems. gzip --best --force filename.html This compresses the file as good as it can (–best) and overwrite a .gz file if it already exists (–force). Brotli Brotli is a fairly new kid on the block when it comes to compressing files.

Why block POST requests in the first place? Some websites or resources don’t need POST requests, such as a statically generated website. It looks like POST requests also take some CPU time within nginx to process them compared with static files. This becomes visible when using the $request_time variable to customize the access log. 2024-04-02T10:14:39+00:00 404 a.b.c.d “POST /xmlrpc.php HTTP/1.1” 562 “-” “Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.

On invitation by the Dutch consultancy firm Snow (now SUE), I attended their Snow Unix Event (SUE). It was the third time in a row, with again an impressive lineup of speakers. As I worked previously for the company, I expected no less than that. The theme was about knowledge sharing. That sounds like an invitation to also share some of the biggest insights I learned. Let’s start with the HTTP/2 insights by Daniel Stenberg.

Recently we changed our corporate website into a “HTTPS only” version. Most of the content is not secret information, still we have some sensitive areas. The ordering section and downloads, and additional our portal. While some areas were already covered with a lock, we felt it was time to make the jump to cover it all. Additionally, we believe that we doing everything we can on our website, practicing security hardening ourselves.

OCSP stapling is a logical follow-up on Online Certificate Status Protocol. OCSP itselfs just checks if certificate is still valid by determining if it is on a revocation list. The original OCSP protocol forces the client to check for the status of a certificate. This results in a lot of traffic for the CA behind the certificate. OCSP stapling moves the check to the owner of the certificate. On a regular basis the Nginx server will perform the check, receiving a new OCSP response.

What is this BEAST? BEAST, or “Browser Exploit Against SSL/TLS” is an attack against the cipher block chaining (CBC) method used with SSL/TLS. The weakness was discovered in 2002, but finally proven in 2011 by security researchers Thai Duong and Juliano Rizzo. With real proof of concept code, they showed it was no longer a theoretical attack. To successfully perform the BEAST attack, there are some conditions which needs to be met:

Configure Apache or Nginx to use HTTP Strict Transport Security (HSTS)

If you care about security, making your system “lean” is one very good start. Remove all clutter, like unused packages. It is part of system hardening and considered a good practice. This also applies to leaking of version numbers, which can only be harmful. Yes.. it is security through obscurity. But why would you reveal specific details about your environment to attackers? In this article we have a look at the very popular Nginx web server daemon.