System Intrusion

1. What is system intrusion?

Computer hackers are able access the information stored on computers, if these aren't properly protected. Hackers often do this using automated intruder programs. These programs usually look for 'Trojans' installed on people's computers.

2. What are Trojans?

These are a type of virus. They pretend to look like legitimate programs or utilities (e.g. a screensaver, game etc.) and silently destroy files or unlock a 'back door', giving a hacker easy access to your computer system and personal information. Trojans can:

• Steal private information - e.g. bank and credit card details, usernames and passwords
• Corrupt or destroy information on your computer
• Take control of your computer to hack into other systems

How can a Trojan get into my computer?

Trojans are usually found as executable files - attached to emails or as website downloads (e.g. mp3s, tools, or games). Be very wary of opening files with .exe, .com, .bat and .vbs extensions, unless you're certain they are harmless and come from a safe source.

Also watch out for hidden file extensions. By default Windows hides the last extension of a file (e.g. what may seem to be a harmless picture - 'photo.jpg' could actually be 'photo.jpg.exe' - a Trojan).

How do I find out if I've got a Trojan?

If you think that an attempt to access your computer has been made you should run a full virus check immediately (Make sure that your virus software is up-to-date before doing this).

3. Securing your system - Firewalls

A firewall blocks unauthorised access to computers over a network, locking the door to unwanted intruders and stopping them scanning your computer.

Firewalls keep a log of the incoming and outgoing connection attempts to and from your computer. Hardware or software-based, a firewall is the ultimate tool in the defence of your system.

• Home users: a software firewall is cheap and effective solution
• Business users: a hardware solution is advised as they offer the best defence

Most versions of Windows have a built-in firewall, however, this only monitors incoming activity. Some forms of intrusion can use your computer's outgoing data, so a fully featured firewall is always the best option.

A free firewall system is available to all our broadband customers, read more about it here. It's also possible to download low-cost or free personal firewall programs from reliable download sites such as Tucows.

The Plusnet Usertools site is a useful website run by a group of Plusnet customers. They have created a tutorial on security software, including firewalls - Usertools: Essential security software

Wireless Internet users: We recommend that you install a security solution on your device, which provides adequate protection against viruses and system intrusion. Also:

• De-activate any automatic log-in facilities (e.g. passwords)
• Where possible - use a secure Virtual Private Networking (VPN) to connect to a corporate network
• When banking online, check for the padlock icon on your browser. Click on it, to prove that the website is genuine and secure

4. Safety Tips

Do

• Use a firewall. Switch on the built-in firewall if available - Learn how to activate the built-in Windows firewall
• Create user accounts and assign a password to the guest account to restrict access to information
• Use a router for broadband connectivity. This makes your computer invisible to Internet users and more resistant to attack. However, firewalls can make some legitimate activities such as hosting services or network computer games more difficult
• Consider upgrading your operating system if you're still using an older version of Windows. Newer versions of Windows offer increased security and are harder for hackers to exploit

Don't

• Use an Administrator account for everyday work, try to use the Limited account instead. Limited accounts are restricted which can heavily reduce the effectiveness of malicious software
• Download, open or preview any file that you're not sure about. Even if files come from family or friends you need to make sure that these aren't Trojans in disguise. You should scan the attachment with your anti-virus program and if in doubt double-check with the sender what the file actually is