Internet threats

A computer virus attaches itself to a program or file enabling it to spread from one computer to another, leaving infections as it travels. Like a human virus, a computer virus can range in severity: some may cause only mildly annoying effects while others can damage your hardware, software or files. Almost all viruses are attached to an executable file, which means the virus may exist on your computer but it actually cannot infect your computer unless you run or open the malicious program. It is important to note that a virus cannot be spread without a human action, (such as running an infected program) to keep it going. Because a virus is spread by human action people will unknowingly continue the spread of a computer virus by sharing infecting files or sending emails with viruses as attachments in the email.

A worm is similar to a virus by design and is considered to be a sub-class of a virus. Worms spread from computer to computer, but unlike a virus, it has the capability to travel without any human action. A worm takes advantage of file or information transport features on your system, which is what allows it to travel unaided.

The biggest danger with a worm is its capability to replicate itself on your system, so rather than your computer sending out a single worm, it could send out hundreds or thousands of copies of itself, creating a huge devastating effect. One example would be for a worm to send a copy of itself to everyone listed in your e-mail address book. Then, the worm replicates and sends itself out to everyone listed in each of the receiver's address book, and the manifest continues on down the line.

Due to the copying nature of a worm and its capability to travel across networks the end result in most cases is that the worm consumes too much system memory (or network bandwidth), causing Web servers, network servers and individual computers to stop responding. In recent worm attacks such as the much-talked-about Blaster Worm, the worm has been designed to tunnel into your system and allow malicious users to control your computer remotely.

A Trojan Horse is full of as much trickery as the mythological Trojan Horse it was named after. The Trojan Horse, at first glance will appear to be useful software but will actually do damage once installed or run on your computer. Those on the receiving end of a Trojan Horse are usually tricked into opening them because they appear to be receiving legitimate software or files from a legitimate source. When a Trojan is activated on your computer, the results can vary. Some Trojans are designed to be more annoying than malicious (like changing your desktop, adding silly active desktop icons) or they can cause serious damage by deleting files and destroying information on your system. Trojans are also known to create a backdoor on your computer that gives malicious users access to your system, possibly allowing confidential or personal information to be compromised. Unlike viruses and worms, Trojans do not reproduce by infecting other files nor do they self-replicate.

Added into the mix, we also have what is called a blended threat. A blended threat is a more sophisticated attack that bundles some of the worst aspects of viruses, worms, Trojan horses and malicious code into one single threat. Blended threats can use server and Internet vulnerabilities to initiate, then transmit and also spread an attack. Characteristics of blended threats are that they cause harm to the infected system or network, they propagate using multiple methods, the attack can come from multiple points, and blended threats also exploit vulnerabilities.

The first step in protecting your computer from any malicious there is to ensure that your operating system (OS) is up-to-date. This is essential if you are running a Microsoft Windows OS. Secondly, you need to have anti-virus software installed on your system and ensure you download updates frequently to ensure your software has the latest fixes for new viruses, worms, and Trojan horses. Additionally, you want to make sure your anti-virus program has the capability to scan e-mail and files as they are downloaded from the Internet, and you also need to run full disk scans periodically. This will help prevent malicious programs from even reaching your computer.

You should also install a firewall. A firewall is a system that prevents unauthorized use and access to your computer. A firewall can be either hardware or software. Hardware firewalls provide a strong degree of protection from most forms of attack coming from the outside world and can be purchased as a stand-alone product or in broadband routers. Unfortunately, when battling viruses, worms and Trojans, a hardware firewall may be less effective than a software firewall, as it could possibly ignore embedded worms in out going e-mails and see this as regular network traffic.

(based on: https://www.webopedia.com)

18. Find English equivalents in the text above:

Варіювати за важкістю, виконуваний файл, шкідлива програма, запустити інфіковану програму, позбавлений допомоги, копіюватися, руйнівний вплив, прокладати хід, обман, бекдор, ставити під загрозу, групувати, вразливість, гарантувати, широкосмугові маршрутизатори, мережевий трафік, прихований хробак, складна атака, докучливий, споживати занадто багато пам’яті, боротися з вірусами, прикріплення, запобігати.

19. Fill in the gaps with the appropriate words:

1. An unauthorized program that inserts itself into a computer system and then propagates itself to other computers via networks or disks is a ________.
2. A computer program that checks a computer for viruses and prevents their spread is an _________.
3. Your anti-virus program has the capability to ______ e-mail and files as they are downloaded from the Internet.
4. A _______ is a system that prevents unauthorized use and access to your computer.
5. A program that appears to be legitimate but is designed to have destructive effects is a ________.
6. Trojans are also known to create a _______ on your computer that gives malicious users access to your system.
7. The biggest danger with a worm is its capability to ______ itself on your system.
8. I find adware really ________.
9. The worm _________ too much system memory.
10. The first step in protecting your computer from any malicious there is to ensure that your _________ is up-to-date.