Getting virus to the system has become common for everyone who uses system regularly. Some virus harms more or some less; if virus attack is minor then that can be cleaned out from the system, but if the attack is major then that can corrupt the system hard drive and confidential data.
To protect your system from risk, install clean-up and antivirus to your system, but sometime your system goes into the situation where antivirus gets fail and virus on the system corrupt the whole system in the presence of antivirus.
The installation of antivirus to the system is totally depends on what kind of work you do on your system. If you use your system for confidential data then you must have to go for any paid and strongly effective antivirus or if you are using your system for common chat and communication then you can go for free antivirus.
Here, I have highlighted some worst and notorious computer viruses that can become a reason of lots of damage in real life. Since, users always complain about malware “worms” and “Trojan” house, I am including these two also in this list,
1# ILOVEYOU
After a year, when the Melissa virus attacked on the Web, Philippines developed a digital menace had come up in the form of a standalone worm program skilled of duplicate itself, later it has given the name ILOVEYOU.
Initially, similarly like the Melissa virus, the ILOVEYOU virus was travelled through e-mail with the subject “a love letter” from a secret admirer and attachment “LOVE-LETTER-FOR-YOU.TXT.vbs”, this attachment was causing all the trouble. “LOVE-LETTER-FOR-YOU.TXT.vbs” extension (vbs) points to the language (Visual Basic Scripting) the hackers used to create the worm. Approximately, it damaged $10 billion of Windows system.
McAfee, an anti-virus software creator said that the ILOVEYOU virus attack is wider – it can copy it-self several times and hide those copies in many folders of the hard drive, adds new files to the registry keys, exchanges several different files with copies of itself, and sent itself through Internet Relay Chat clients and e-mail.
2# Code Red
In 2001, Code Red was first exposed by two eEye Digital Security employees. The name has given Code Red because the pair was drinking Code Red Mountain Dew during discovery. Thus, it runs totally on memory, with a size of 3,569 bytes, leaves very little hint on the hard disk. Effect of this virus can byte lots of the systems resources and can make hundreds of copy of itself that spreads to many system resources.
3# CryptoLocker
Be careful, there is a big threat (ransomware) over the internet called Cryptolocker that infected many organization and communities.
Usually, Cryptolocker comes through social engineering. This virus comes in the form of executable attachment and the icon of the executable file will be in PDF format. Windows’ hidden extensions feature easily hides “.exe” file extension, so that; sender can easily hide and send the “.pdf” file with the attachment to the receiver thinks the file that has been come from the sender is an important “.pdf” file.
If, your system is captured by Cryptolocker will target your system with the following extensions,
.ai, .indd, .cdr, .jpg, .jpe, img_.jpg, .dng, .3fr, .arw, .srf, .odt, .ods, .odp, .odm, .odc, .odb, .doc, .docx, .docm, .wps, .xls, .xlsx, .xlsm, .dxf, .dxg, .wpd, .rtf, .wb2, .mdf, .dbf, .psd, .pdd, .pdf, .eps, .xlsb, .xlk, .ppt, .pptx, .pptm, .mdb, .accdb, .pst, .dwg, .orf, .raf, .raw, .rwl, .rw2, .r3d, .ptx, .pef, .srw, .x3f, .der, .cer, .crt, .pem, .pfx, .p12, .p7b, .p7c, .sr2, .bay, .crw, .cr2, .dcr, .kdc, .erf, .mef, .mrw, .nef, .nrw.
4# Sasser
Sasser is a computer worm that attacks on the weakest version of Windows operating system “Windows XP” and “Windows 2000” through the network port. How fast it comes through network port that much fast it can be removed through firewall or by downloading system updates from Windows Update.
Sasser was first detected and started scattering on April 30, 2004. It has given the name Sasser because it spreads by misusing a buffer overflow on the element LSASS (Local Security Authority Subsystem Service) on the pretentious operating systems.
Conclusion
Apart from these all, there are many more computer virus that can corrupt your whole system or system important data. Protect your system from those viruses by installation and uses of clean-up and antivirus tools and update them in case of any update comes up.
