Hacked off
Internet security, or rather the lack of it, is the bane of today’s computer user.
Computer hackers write malicious computer programs (or malware) that infect vulnerable computers and modify the way they operate. Typically, these programs are downloaded from the internet inadvertently with a single click of the mouse. The consequences are detrimental to the user, ranging from a minor nuisance – for example, slowing the computer’s speed – to a major financial loss for an individual or company, when login and password details are accessed and fraud ensues.
Examples of malware include viruses, worms, trojans (Trojan horses), spyware, keystroke logging, scareware and dishonest adware.
A virus can be released when a user opens an email and downloads an attach
ment. The text portion of the email cannot carry any malware but the attachment may contain a virus, for example in a macro (a short program) embedded in a worksheet document, such as Excel. Viruses can replicate and if they spread to the host com
puter’s boot sector files they can leave the user with a ‘bluescreen of death’. In this circumstance, the bluescreen is accompanied by a message that starts ‘A problem has been detected and Windows has been shut down to prevent damage to your computer’. Whilst malware cannot physically damage the computer’s hard drive the information on the boot sector has been destroyed and the computer is unable to function. In a worst case scenario the hard disk has to be wiped clean by reformatt
ing, before the operating system can be reinstalled, in which case every program and file will be lost.
Unlike a virus, a worm can infect a computer without the user downloading an attachment, so it can spread through a network of computers at tremendous speed. The ability of worms to replicate in this way means that they can infect every contact in the user’s email address book and potentially every email contact in each recipient’s computer. Instant messaging programs and social networking sites are similarly at risk. A main feature of a worm is that it slows the computer down by consuming memory or hard disk space so that the computer eventually locks up.
The word trojan derives from the Trojan Horse of Greek mythology that tricked the Trojans into allowing Greek soldiers into the city of Troy, hidden inside a wooden horse. Today a trojan is a metaphor for malware that masquerades as useful software.
Trojans are unable to replicate but they interfere with the computer surreptitiously, allowing viruses and worms unfettered access to the system.
Spyware programs monitor a computer user’s internet surfing habits covertly.
Some spyware simply monitors how many visits consumers make to particular web pages and what they are buying or spending, usually for marketing purposes.
Keystroke logging is the main fraudulent activity linked to spyware. Here, private and confidential information is obtained from the user’s keystrokes, enabling criminals to acquire credit card details, or login names and passwords for online bank accounts.
Some keystroke loggers operate legitimately to monitor the internet use of employees in the office or to keep tabs on children’s surfing activities at home.
Scareware is a form of extortion where a victim is informed that the computer is infected with a virus and, for a fee, is offered a solution to fix the problem. The user is tricked into clicking an ‘OK’ button and buys software unnecessarily because there is usually no virus. In one scam, a scareware popup informs the victim that the computer’s registry contains critical errors when the problems are actually minor or even nonexistent. Persuaded by the popup advert, the victim buys the ‘registry cleaner’, which may not work or could even damage the computer’s registry. There are of course legitimate registry cleaners that will boost your computer’s speed.
A genuine registry cleaner will normally be endorsed by a reputable company or recommended in a PC magazine.
Adware popup adverts are similar to scareware but are merely a nuisance rather than malware (unless dishonest), though they can still download programs that track your shopping habits and slow your computer down. The adverts pop up auto
matically when the user opens the internet browser and can become irritating because they conceal information on the opened up page. One answer is to turn on the Internet Explorer’s popup blocker under the privacy tab because this will block most automatic popups. More effectively, a user can purchase an allinone security suite to block any malware. Security software automatically blocks and deletes any malicious programs for a more secure web experience. Normally, the software will update itself every day as long as the computer is switched on.
Questions 281 to 287
Do the following statements agree with the information given in Reading Passage 10?
Write:
TRUE if the statement agrees with the information FALSE if the statement contradicts the information NOT GIVEN if there is no information on this.
281 Malware is usually downloaded from the internet by mistake.
282 An email text can carry a virus.
283 A virus can result in the loss of every program and file.
284 Java applets can contain malicious code.
285 A Trojan disguises itself as useful software.
286 Keystroke logging is always fraudulent.
287 Scareware is not harmful to the user.
Questions 288 to 292
Classify the following as typical of A a virus
B a worm
C a virus and a worm.
288 requires user input to infect a computer.
289 can duplicate itself.
290 reduces the computer’s speed.
291 do not damage the hard drive.
292 can be removed by security software.