Introduction

The topic of the blog post is applied IT Security on Linux Ubuntu Desktops. IT security is a hot topic since all the aspects of our live is based on IT in one form or another. Many companies around the world are affected by attacks against their IT systems and these attacks do a huge harm and cost a lot of money.

On one side systems and data security is a challenge for companies but on the other side also private individuals are seeking for security and want to have safe IT systems.

Ubuntu Desktop and Linux Desktop users are less exposed to cyber threads than Windows users but Microsoft also geared up its recent Windows versions regarding to IT security.

From my experience I can say that mostly an odd behavior of a Linux desktop system is caused by a software bug rather than a hacker, a virus, a rootkit or another malware. That applies to Windows too.

But to be sure it’s always good to know how to check your Ubuntu PC or Linux Desktop for malware and keep it safe. That’s why I want to introduce 4 Linux IT security tools to you. They are:

• Rookit Hunter which is a malware scanner
• ClamAV, an anti virus software
• Chkrootkit, another malware scanner
• UFW, stands for uncomplicated firewall

Let’s start with Rootkit Hunter:

Rootkit Hunter

A rootkit is a malicious software which grants a hacker full access to an IT System. There are a lot of different rootkits around for Linux systems.

There is a software for detecting rootkits on Linux systems which is called Rootkit Hunter.

First of all, if we want to use Rootkit Hunter, we need to install it by opening a terminal and and we need to execute:

sudo apt-get install rkhunter

As a next step we need to update Rootkit Hunter:

sudo rkhunter --update

Then we have to do a check of our Linux (Ubuntu) system with:

sudo rkhunter -c

Several checks are done then on the Linux system.

Often Rootkit Hunter doesn’t run immediately after the installation and gives us some errors.

Learn here how to fix WEB_CMD, Update failed, SCRIPTWHITELIST errors.

We learn about a Linux anti virus software next.

ClamAV

ClamAV is the Linux anti virus software which is available since more than two decades. There are every now and then proprietary anti virus solutions for Linux popping up for a short period of time. I have seen Linux versions from the anti virus software vendors Sophos, AVG, Avira and so on. But after so short time these products were vanishing.

So ClamAV is the most reliable anti virus software for Linux. Let’s learn how to install it on Ubuntu:

sudo apt-get install clamav

Next we need to update the virus definitions:

sudo freshclam

Then we are able to scan a directory with the following command and its options:

clamscan /home –recursive=yes –infected

The parameter “–recursive” means that also sub directories of /home are scanned. The option ” –infected” means that there is only output in the terminal if a virus was found. /home is our directory which we want to be scanned.

So far, so good. Now we are learning about another rootkit scanner – Chkrootkit.

Chkrootkit

Chkrootkit is like Rootkit Hunter a detection software for rootkits on Linux systems.

Since rootkits are often hiding themselves on infected system it could be a good approach to scan the system (the file system) with a Linux live system. Find the instruction here!

The first step is to install Chkrootkit on Ubuntu:

sudo apt-get install chkrootkit

Then do the check with:

sudo chkrootkit 

Here you are seeing if there are finds or suspicious files on the computer. As next we learn about a firewall.

UFW – Uncomplicated Firewall

Not only scanning a system and detecting malicious software is important for systems and data security. Also protecting our services on our Linux system with a firewall is an important prevention and security measure.

Depending on our systems setup probably several services (servers, also called daemons ) are active on our Linux. It could be the SSH server (Secure Shell Server) or any other service. We want to protect these services with a firewall.

The most firewall products need a deeper understanding of networking and networking technologies. But there is a simple solution available for Linux called “UFW – Uncomplicated Firewall”. If installed and activated it blocks incoming network traffic by default and allows all the outgoing network traffic.

Let’s install UFW with “apt-get”:

sudo apt-get install ufw

Then we need to enable the UFW with:

sudo ufw enable

To get more detailed information type:

ufw status verbose

You will see these lines in the output:

Status: active
Logging: on (low)
Default: deny (incoming), allow (outgoing), disabled (routed)
New profiles: skip

Conclusion

I introduced 4 important tools to you and I showed you how to install and configure these tools. The rootkit scanners are a good starting point if a systems show an odd or suspicious behavior. And ClamAV is a stable project since many years. It’s always good to have a firewall enabled and UFW is really easy to enable and to handle.

Feel free to comment this post!

WordPress is a software which was initially designed for blogging (weblog) purposes. A blog software can be used to publish content chronologically to the internet. Over the time and with ongoing releases WordPress developed and nowadays it can be used as a basis for ordinary webpages. It can be used similar as Joomla! or Drupal or even Bootstrap (HTML and CSS).

If you want to run your own blog or a small webpage WordPress is first choice.

To customize the base system, a broad range of themes and plugins can be installed. Most of them are free and only advanced use costs money.

WordPress is popular because first successes can be achieved easily a no software development skills are required to set up a nice little web page.

The development of WordPress goes on and the current version is 6 and its sub versions. WordPress is based on PHP and runs on the Apache2 web server and on Linux. This tutorial shows the installation of WordPress on Ubuntu Linux.

1. Install Software

First of all we need to install software on our Ubuntu. Open a terminal and type the following lines to have a web server (Apache2), a database (MySQL) and PHP installed:

sudo apt-get --yes install mysql-server apache2 
sudo apt-get --yes install libapache2-mod-php php-mbstring 
sudo apt-get --yes php-xml php-intl php-mysql
sudo a2enmod php7.4

2. Create the MySQL Database

Now we need to run the MySQL Command Line Interface (CLI). Therefor we need to execute in a terminal:

sudo mysql -u root -p

We are in the MySQL CLI now. Type:

mysql> CREATE DATABASE wordpress;

As the next step, we need to create a user, grant the necessary permissions to the user and at the same time we are setting a password:

mysql> CREATE USER 'wordpress'@'localhost' IDENTIFIED BY 'secpasswd';
mysql> GRANT ALL PRIVILEGES ON wordpress.* TO 'wordpress'@'localhost';

And then we quit the MySQL CLI:

mysql> FLUSH PRIVILEGES;
mysql> quit

3. Download WordPress to the right Directory

Now we need to download and extract WordPress in a terminal/shell with these commands:

cd /var/www/html
sudo wget https://wordpress.org/latest.zip
sudo unzip latest.zip

To not run into an error during the installation, the ownership for the WordPress directory has to be changed. On my Ubuntu system the “www-data” user and the “www-data” group need to have the ownership of the directory structure. Run the following command:

chown -R  www-data:www-data /var/www/html/wordpress

6. Install and Configure WordPress

Next, open an internet browser and connect to “http://localhost/wordpress”.

Select a language and click on “Let’s go!”. Now the fine tuning has to be done. Provide these settings:

Database: "wordpress" 

Username: "wordpress"

Password: "secpasswd"

Database Host: "localhost"

Click to “Submit” and on the next page “Run the installation”.

Provide now “Site Title”, the WordPress “Username”, a secure WordPress password, your email address and click to “Install WordPress”.

Conclusion

Congratulations! You successfully installed WordPress on your Ubuntu computer! Open a browser and connect to “http://localhost/wordpress/” and login. You can check out now the backend of WordPress and you have a basic site set up for future customization.

Continue with installing themes and plugins and the configuration of menus. It’s just easy to go on from this point.

If you are interested in other CMS, check out my Joomla!, CMSimple or Confluence tutorials!

Feel free to comment this post!

Basic Information

Many websites in the internet run on Content Management Systems (CMS) nowadays. A CMS provides a relatively easy way to publish web content to the internet. The good thing about a CMS is that no software development skills are necessary. Although there are often good templates and plugins provided the fine tuning to have a CMS with a fancy design still can be tricky.

CMS with high market shares are WordPress, Drupal and Joomla!. These names are around all the time when it is about CMS and web page development. These systems are put on web servers like the Apache web server and they use a database system like MySQL to store the content like blog posts and pages in it.

I am sure there are use cases for CMS where it can be an advantage to not store content in a database system. Webhosters for example limit the amount of available databases to their customers – means in short: more databases cost more money.

I want to introduce a CMS which doesn’t need a database to store its content. The name of the CMS is “CMSimple”. All the pages and the contents of CMSimple are stored in files. The next paragraphs show the procedure to have CMSimple up and running.

Here are the steps I took to install CMSimple on a Ubuntu PC for test purposes:

1. Download

Open a terminal and download the Zip File from the CMSimple download page:

sudo wget https://www.cmsimple.org/downloads_cmsimple50/CMSimple_5-8.zip /tmp

sudo unzip /tmp/CMSimple_5-8.zip

2. Install the Apache2 Web Server

sudo apt-get --yes install apache2 apache2-data apache2-utils
sudo apt-get --yes install libapache2-mod-php

The command above installs the Apache web server on Ubuntu. The next command starts the web server:

sudo service apache2 start

3. Put the CMS on the Webserver

Now the downloaded and extracted files need to be put to the web server directory and permissions need to be modified:

sudo mkdir /var/www/html/cms
sudo cp -r /tmp/CMSimple_5-8/* /var/www/html/cms/
sudo rm -rf /var/www/html/cms/2*
sudo cp /var/www/html/cms/setup/setupControl.php /var/www/html/cms/
sudo chown -R www-data:www-data  /var/www/html/cms/*

4. Login and change the Password

The developers of CMSimple write on their page that there is a limit of 5 minutes for you to change the password. After that time you have to start all over again.

So open a browser and type the following URL to the address line of the browser:

http://localhost/cms/setup.php

Set a password with at lease 5 positions. I personally recommend to set a 16 positions complex password on production pages.

On the next screen type the same password in to the “Password:” input box. Leave the “User (optional):” input box blank.

Conculsion

Now the hard work just starts. Customize your page with text, images and all the stuff a fancy page requires. As mentioned above the content is just stored in the file system. This can be also an performance advantage and the loading time could be reduced compared to other extensive CMS.

If you are doing a technology evaluation currently, give CMSimple a chance. Small web projects could be done for sure with this CMS. New designs, so called templates, can be easily created for CMSimple.

If you are interested in a CMS with a database as a data storage, check out my WordPress, Joomla! or Confluence tutorial!

Have fun 😊

Basic Information

Confluence is a Wiki system comparable with MediaWiki. In companies it is used for documentation purposes and as an information hub. It is basically a commercial software and Atlassian is the company behind it. It is possible to have a free installation with some limitations or to buy a license to have an instance with full features. Confluence is proprietary software written in Java.

The data store which holds basically the majority of the web content of Confluence is in our case MySQL. MySQL is available in the Ubuntu repositories.

Please notice that a productive installation needs to have a good planning. I provide here a good first impression on how to do a successful setup of a test instance of Confluence.

1. Install Software

On Ubuntu the prerequisite to have Confluence finally up an running is to have these packages installed by Terminal/Shell:

sudo apt-get --yes install mysql-server

2. Create a MySQL Database

After we have installed the MySQL Ubuntu package we need to create a database and an user and grant access to the user with the MySQL Command Line Interface (CLI). First log in with empty password:

sudo mysql -u root -p

Then create a database with the name “confluence”:

mysql> CREATE DATABASE confluence;

The next command creates a user called “confluence” with the password “secpasswd”. And the user gains access to the database:

mysql> GRANT ALL PRIVILEGES ON confluence.* TO confluence@localhost IDENTIFIED BY 'secpasswd';

Exit the MySQL CLI:

mysql> FLUSH PRIVILEGES; 
mysql> quit

After this stay in the Terminal/Shell and run this command:

sudo echo transaction-isolation=READ-COMMITTED >>/etc/mysql/mysql.conf.d/mysqld.cnf

This step is required. If not done the installation will fail later on.

3. Download Confluence

To download Confluence run in a Terminal/Shell:

wget https://product-downloads.atlassian.com/software/confluence/downloads/atlassian-confluence-7.20.1-x64.bin -O /tmp/atlassian-confluence-7.20.1-x64.bin

Now is is necessary to set the right permissions to the downloaded file to make it executable:

chmod a+x /tmp/atlassian-confluence-7.20.1-x64.bin

4. Start the Installation

To start the installation procedure run in a Terminal/Shell:

sudo /tmp/atlassian-confluence-7.20.1-x64.bin

Fontconfig and Jave Runtime Environment (JRE) are configured. The next steps are summarized on a screenshot. The configurations are red marked:

We did an “Express Install” and Confluence is now accessible by an internet browser and the address “http://localhost:8090”. The installation continues now by browser.

I recommend for testing purposes to choose:

Trail Installation

A link is provided to Atlassian.com to register for a trail license. This can be done easily with a Google Account. After setting the trail license choose:

Non-clustered (single node)

Next it’s about the database settings. Use “MySQL”, open a Terminal/Shell and do the following:

wget https://cdn.mysql.com/archives/mysql-connector-java-5.1/mysql-connector-java-5.1.49.zip -O /tmp/mysql-connector-java-5.1.49.zip
unzip /tmp/mysql-connector-java-5.1.49.zip -d /tmp
sudo cp /tmp/mysql-connector-java-5.1.49/mysql-connector-java-5.1.49-bin.jar /opt/atlassian/confluence/confluence/WEB-INF/lib
sudo service confluence restart

Refresh the browser and continue with “MySQL” and insert the following data into the appropriate fields:

Setup type: "simple"

Hostname: “localhost”

Port: "3306"

User: “confluence”

Database name: “confluence”

Password: “secpasswd”

Click on “Next”

On the “Load Content” Page, let’s set up an “Example Site”.

On the “Configure User Management” page I selected “Manage users and groups within Confluence. I set on the “Configure System Administrator Account” my username, email and password. Then I got “Setup Successful” and clicked to “Start”.

Conclusion

The setup can be very tricky but finally we got a good first impression and a solid test environment. Maybe several health check messages are popping up and some optimizations need to be done. Since Confluence is not completely free, MediaWiki or XWiki could be an alternative. As I wrote above a free license with several restrictions is offered by Atlassian.