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Showing posts with the label COMPUTER VIRUSES

What Is A Computer Virus ? Causes of Computer Virus ? Types of Computer Virus

What Is A Computer Virus? A Computer Virus is a malicious software program “Malware” that can infect a computer by modifying or deleting data files, boot sector of a hard disk drive or causes a software program to work in an unexpected manner”. A computer virus resides on a host computer and can replicate itself when executed. Virus can steal user data, delete or modify files & documents, records keystrokes & web sessions of a user. It can also steal or damage hard disk space, it can slowdown CPU processing. Activation of Virus When the computer virus starts working, it is called the activation of virus. A virus normally runs all the time in the computer. Different viruses are activated in different ways. Many viruses are activated on a certain data. For example, a popular virus  “Friday, the 13 th ” is activated only if the date is 13 and the day is Friday. According to Wikipedia “Computer viruses cause billions of dollars’ worth of economic damage each year, due to causing...

What Is Ransomware? How Does Ransomware Work?

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What is Ransomware? Ransomware is a malicious software that carries out the cryptoviral extortion attack from cryptovirology that blocks access to data until a ransom is paid and displays a message requesting payment to unlock it. Simple ransomware may lock the system in a way which is not difficult for a knowledgeable person to reverse. More advanced malware encrypts the victim's files, making them inaccessible, and demands a ransom payment to decrypt them. The ransomware may also encrypt the computer's Master File Table (MFT) or the entire hard drive. Thus, ransomware is a denial-of-access attack that prevents computer users from accessing files since it is intractable to decrypt the files without the decryption key. Ransomware attacks are typically carried out using a Trojan that has a payload disguised as a legitimate file. How Does Ransomware Work? Ransomware gains access to a computer the same way as any kind of virus or computer worm - either through getting the user to ...