Modern technology brings modern dangers and we are all exposed on a daily basis, whether we realise it or not. Gone are the days when all you had to worry about was the phone ringing and upon answering heard a moment of heavy breathing followed by “what ya wearing”. Now, your PC, Smart Television, Mobile Phone and many other devices are connected to the internet all day long and each of them may be vulnerable to attack.
For now we will only cover your PC because attacking your television or refrigerator isn’t likely to cause your credit card or identity to be stolen.
The internet works for you because some very clever people figured out how to make all the different things you can do work together with only one internet connection in the back of your computer. They did this by creating individual protocols such as http, smtp, pop, ftp and bucket loads more. The protocols you use most of the time will be http (Hyper Text Transfer Protocol) for requesting web pages or perhaps it’s secure counterpart https. Each protocol has an assigned Port Number and your computer listens for properly formatted activity on various ports number 1- 65535. Generally speaking, as a home user you will not have port 80 (http) opened unless you run a web server and in fact many ISP’s will close port 80 and a number of others too.
These ports are useful for hackers who scan the internet looking for open ports on random computers around the world.
A colleague performed an experiment and opened up port 22 for 24 hours. Port 22 is used for Secure Shell allowing remote access to servers and is very dangerous when not configured properly. Access attempts were logged to a file for later review and the results were shocking. There were many thousands of hack attempts from over 900 individual IP Addresses. The majority of those hack attempts came from Russia, China and the United States. Had their attempts been successful the hacker would have gained full access to the server and have the ability to create & delete users, copy all the data they wanted and then gone about their normal lives.
FIREWALLS A NECESSARY EVIL
Microsoft Windows comes with a basic firewall, so don’t panic right away. A firewall sits between you and the internet and listens on all ports for activity, blocking access attempts you have not allowed.
In addition Firewalls can also monitor outgoing traffic. That is an excellent method for preventing unknown or unwanted applications accessing the internet. You may have inadvertently downloaded a melicious software package or clicked on a link in a dodgy email and released a worm or virus onto your computer. When that little bugger attempts to make contact with a remote computer, perhaps to allow hackers to remotely control your computer, the firewall will display a message giving you an opportunity to deny access.
What a firewall wont do is prevent you clicking on a dodgy email which then uses your email software to spread itself to everyone in your address book. For email to work you must allow it through the firewall, and therefore a clear path in and out of your computer exists and the firewall can do nothing about it.
Vigilance is your best friend. Firewalls and Antivirus packages are a fact of life in the 21st century and all you can is arm yourself with defensive weapons to minimise your exposure.
When that doesn’t work, call me and I’ll clean up your computer and ensure you have appropriate protection.