Security

What the Red Means> What the Red Means # The lines that the user needs to enter or customize will be in red in this tutorial! The rest should mostly be copy-and-pastable.

Status: Deprecated> Status: Deprecated # This article covers a version of Ubuntu that is no longer supported. If you are currently operate a server running Ubuntu 12.04, we highly recommend upgrading or migrating to a supported version of Ubuntu:

Introduction> Introduction # On September 24, 2014, a GNU Bash vulnerability, referred to as Shellshock or the “Bash Bug”, was disclosed. In short, the vulnerability allows remote attackers to execute arbitrary code given certain conditions, by passing strings of code following environment variable assignments.

Introduction> Introduction # UFW, or Uncomplicated Firewall, is an interface to iptables that is geared towards simplifying the process of configuring a firewall. While iptables is a solid and flexible tool, it can be difficult for beginners to learn how to use it to properly configure a firewall.

Status: Deprecated> Status: Deprecated # This article covers a version of CentOS that is no longer supported. If you are currently operating a server running CentOS 6, we highly recommend upgrading or migrating to a supported version of CentOS.

Introduction> Introduction # In this tutorial, we will go over how to use Tinc, an open source Virtual Private Network (VPN) daemon, to create a secure VPN that your servers can communicate on as if they were on a local network.

Status: Deprecated> Status: Deprecated # This article covers a version of Ubuntu that is no longer supported. If you are currently operate a server running Ubuntu 12.04, we highly recommend upgrading or migrating to a supported version of Ubuntu:

Introduction FTP, short for File Transfer Protocol, is a network protocol that was once widely used for moving files between a client and server. It has since been replaced by faster, more secure, and more convenient ways of delivering files.

Introduction> Introduction # Setting up a good firewall is an essential step to take in securing any modern operating system. Most Linux distributions ship with a few different firewall tools that we can use to configure our firewalls.

Introduction> Introduction # SSH, or secure shell, is an encrypted protocol used to administer and communicate with servers. When working with a Debian server, chances are you will spend most of your time in a terminal session connected to your server through SSH.

Introduction> Introduction # On October 14th, 2014, a vulnerability in version 3 of the SSL encryption protocol was disclosed. This vulnerability, dubbed POODLE (Padding Oracle On Downgraded Legacy Encryption), allows an attacker to read information encrypted with this version of the protocol in plain text using a man-in-the-middle attack.

Status: Deprecated> Status: Deprecated # This article covers a version of Ubuntu that is no longer supported. If you are currently operate a server running Ubuntu 12.04, we highly recommend upgrading or migrating to a supported version of Ubuntu:

Introduction> Introduction # TLS, or transport layer security, and its predecessor SSL, which stands for secure sockets layer, are web protocols used to wrap normal traffic in a protected, encrypted wrapper.

Introduction> Introduction # Config Server Firewall (or CSF) is a free and advanced firewall for most Linux distributions and Linux based VPS. In addition to the basic functionality of a firewall – filtering packets – CSF includes other security features, such as login/intrusion/flood detections.

Introduction> Introduction # Java Keytool is a key and certificate management tool that is used to manipulate Java Keystores, and is included with Java. A Java Keystore is a container for authorization certificates or public key certificates, and is often used by Java-based applications for encryption, authentication, and serving over HTTPS.

Introduction> Introduction # SSH, or secure shell, is a secure protocol and the most common way of safely administering remote servers. Using a number of encryption technologies, SSH provides a mechanism for establishing a cryptographically secured connection between two parties, authenticating each side to the other, and passing commands and output back and forth.

The author selected the COVID-19 Relief Fund to receive a donation as part of the Write for DOnations program. Introduction> Introduction # At some point, you may find yourself on a network that is insecure or has an overly restrictive firewall and you’ll want to make sure no one is watching your traffic.

Status: Deprecated> Status: Deprecated # This article covers a version of Ubuntu that is no longer supported. If you are currently operate a server running Ubuntu 12.04, we highly recommend upgrading or migrating to a supported version of Ubuntu:

Introduction> Introduction # Let’s Encrypt is a Certificate Authority (CA) that provides a way to obtain and install free TLS/SSL certificates, thereby enabling encrypted HTTPS on web servers. It streamlines the process by providing a software client, Certbot, that attempts to automate most (if not all) of the required steps.

Introduction> Introduction # WordPress is a popular and powerful CMS (content management system) platform. Its popularity can bring unwanted attention in the form of malicious traffic specially targeted at a WordPress site.