Increasing online availability levels

Confidentiality, Integrity and Availability. The CIA acronym is always present in Information Security. The three key security properties that any piece of information has.

This post focuses on increasing availability in a specific scenario: We need to access the Internet and we do not trust the hard disks (maybe they are infected by a piece of malware, maybe there is a keylogger already installed...) of our computer.

Ubuntu releases (e.g. 8.10, 9.04 and 9.10) provide the possibility to create a Startup USB drive with some persistent space to store configuration settings and documents.

The drawback of being persistent is that the risk of infecting also the USB drive exists. However, the advantage of persistence is that we can configure it beforehand so that the Ubuntu installation on it is already aware of our router and network configuration. This is specially welcomed if the ultimate user of the USB drive will be an IT layman.

How to do it? Download the iso image preferred to be installed in the USB, go to System, Administration, USB Startup Disk Creator functionality (option present in Ubuntu 9.04 and 9.10) and configure the wizard similarly to this screenshot.



Keep the newly installed USB drive in a safe place and test it every regularly. One unexpected day, it could become the key to have Internet access available.

Happy New Availability (and 2010)!

Downloading IT security videos and extracting their audio

There is a myriad of IT security related videos available on Internet.

This post deals with how to download flv videos and how to extract their audio so that they can be listened while commuting.

Downloading the video file

First step: Install the flashgot add-on in a Firefox browser.

Second step: Download the video file (flv format). The flashgot site explains the installation of the add-on and its use (basically, left and right click on the flashgot icon in the browser status bar will do).

Third step: Once the flv file is stored locally...

Extracting the audio from the video file

Here are some tips to extract the audio track from the flv file into a mp3 file so that it is ready to be listened to:

user@machine:~$ ffmpeg -i Videofileyouhave.flv -vn -ab 64000 Audiofile.mp3

Maybe parameters in the command line need to be modified according to the parameters of the video file. This line is useful to find out those video file parameters:

user@machine:~$ ffmpeg -i file

After this, depending on the mp3 player that will play the audio, sometimes it is necessary to edit the labels in the mp3 file. In Linux, easytag can do it.

When the mp3 file is not reproducible by a specific mp3 player, the use of the package audacity is required. First, to import the initial mp3 file, second, to label it, and, finally, to be export the audio to a new mp3 file.

The final mp3 file will probably be audible in the player at hand.

Happy listening!

p.s. Special thanks to M.A. for the flashgot tip.

How to upgrade virtualbox 2.8 to 3.0 in ubuntu

It is time to upgrade virtualbox. Normally it is a simple task with simple steps but we have to do them in this order.

In the command line:

Adding the debian repository key to our machine:

user@machine:~$ wget -q http://download.virtualbox.org/virtualbox/debian/sun_vbox.asc -O- | sudo apt-key add -

And installing

user@machine:~$ sudo apt-get install virtualbox-3.0

The Sun VirtualBox item in the Applications, System Tools menu will appear in the next bootup.

Alternatively, you can use the Synaptic Package Manager in the System, Administration menu.

By the way, DJ Soul Rebel asked me to post an entry on how to install BT4 directly in a netbook with no virtual machine involved. I will look into that (as you see, there is no deadline committed ;-)

First security steps after installing an Ubuntu Intrepid machine

Two cents to start securing your Linux Ubuntu Intrepid box: A firewall and an antivirus.

- Install a personal firewall e.g. firestarter
- $sudo apt-get install firestarter will install it (more here)
- More on how to use it here
- I recommend to run it at bootup time for all users (including the non-admin ones). Go to system>preferences>sessions and add /usr/sbin/firestarter
- For the non-admin ones, you need to edit the sudoers file as indicated here
- Use the System > Preferences > Session to include the command sudo firestarter

- Install an antivirus such as clamav
- $sudo apt-get install clamav-daemon
- More on how to do it (checking that it runs, scheduling an update, etc) here


Those are the first steps to keep the machine secure!

Creating & moving a virtual machine

We frequently use virtual machines from where we launch our security tools.

Virtual machine creation
Sometimes we need to create a virtual machine from scratch. Here we provide some initial tips about it:

In our last posting we talked about a simple way to make a physical machine virtual. This time we continue on the virtual world. We use VirtualBox as the platform where we create a virtual machine.

First hint: We recommend to use Sun VirtualBox rather than the Open Source Edition (provided that the license terms fit our needs). Using USB drives is easier in the software from Sun.

We find the instructions to build Sun VirtualBox here. The actual installation of a host operating system is easy following the wizard appearing when we run the Menu item Applications > System Tools > Sun xVM VirtualBox if e.g. we the host OS is Ubuntu.

Second hint: Create a hard disk with the possibility to grow in size i.e. VirtualBox call it a dynamically expandable storage.

Moving a virtual machine
On the source machine...
We copy to a removable media the .vdi file (normally residing on /home/.VirtualBox/HardDisks) - This can be a big file.

Third hint: If we do not see the hidden directories in the Ubuntu file browser, press CTRL + H.

On the destination machine...
We paste the .vdi file on the HardDisks folder in our VirtualBox installation and we start the New Virtual Machine wizard (just pressing New when running Sun xVM VirtualBox) and when we are asked about the hard disk to use, we simply point to the .vdi file we have just moved.

Fourth hint: Installing Guest Additions (use this link to download the software, it is not easy to find it) in the guest OS provide us with more video, audio and storage device recognitions capabilities. However...

Fifth hint: If we move virtual machines from one machine to another, we recommend to uninstall in source and re-install in destination. Guest additions is closely link to the architecture of the host system.

Happy security tool testing in your new virtual environment!