Practical work

Karshi branch of TUIT
Faculty of Computer Engineering
Student of group DI-12-22
Abdumannopov Asadbek
PRACTICAL WORK
From English


Performed by: Abdumannopov A.
IT safety:Viruses.
Source:

WHAT VIRUS?
Computer viruses are small software programs that are designed to spread from one computer to another and to interfere with computer operation. A virus might corrupt or delete data on your computer, use your e- mail program to spread itself to other computers, or even erase everything on your hard disk. Viruses are most easily spread by attachments in e-mail messages or instant messaging messages. That is why it is essential that you never open e-mail attachments unless you know who it's from and you are expecting it. Viruses can be disguised as attachments of funny images, greeting cards, or audio and video files. Viruses also spread through downloads on the Internet. They can be hidden in illicit software or other files or programs you might download. To help avoid viruses, it's essential that you keep your computer current with the latest updates and antivirus tools , stay informed about recent threats , and that you follow a few basic rules when you surf the Internet, download files, and open attachments. Once a virus is on your computer, its type or the method it used to get there is not as important as removing it and preventing further infection.

Dialer&Hijacker.

A spyware dialer is a malicious program that is installed on a computer and tries to use the dialing features to call other numbers, often running up expensive phone bills for the victim. A dialer is unlike other types of spyware, though it is sometimes included with free software-type downloads.
They are difficult threats to detect however, and it is not easy to prove that the dialer has been responsible for running up telephone bills. Similarly, it is difficult to distinguish between a legitimate dialer and a spyware one, something that makes this type of infection hard to identify. Spyware dialers are however easy to eliminate once the file where it resides has been identified.
  Browser hijackers, or simply hijackers, are a type of malware created for the purpose of modifying Internet browser settings without the user’s knowledge or consent. Typically, hijackers change the homepage and default search settings. However, some are known to inject advertisements—thus, they are qualified to be called adware, automatically redirecting users to potentially malicious destinations when they visit certain sites, and sometimes making drastic changes to the affected system. Some hijackers also contain keyloggers, which are capable of recording user keystrokes to gather potentially valuable information they enter into websites, such as account credentials.
Backdoor.

A backdoor virus is malware that allows an unauthorized user into devices, applications, and networks. Attackers can gain backdoor access using a command-line interface or other text-based commands. Backdoor viruses can install a script to facilitate admin access, even after removing the malware. Once a backdoor virus is installed, attackers can log the activity on the computer, steal sensitive data, and delete files.