Top 10 Worst Computer Viruses for 2013

Computer viruses are small software programs or a small code that are designed to distract computer user by spreading from one computer to another and to interfere with computer operations.

Here are the lists of Top 10 Worst Computer Viruses for 2013

Sassar

Sasser is a computer worm that affects computers running vulnerable versions of the Microsoft operating systems Windows XP and Windows 2000. Sasser spreads by exploiting the system through a vulnerable network port (as do certain other worms).

Storm worm

The Storm Worm is a backdoor Trojan horse that affects computers using Microsoft operating systems discovered on January 17, 2007.

PGP Coder

Pretty Good Privacy. Considered the strongest program for encrypting data files and/or e-mail messages on PCs and Macintosh computers. PGP includes authentication to verify the sender of a message and non-repudiation to prevent someone denying they sent a message.

OSX/RSPlug Trojan

The RSPlug Trojan horse, a form of DNSChanger, is malware targeting the Mac OS X operating system. The first incarnation of the trojan, OSX.RSPlug.A, was discovered on October 30, 2007 by the Mac security experts at Intego.

Slammer

The SQL Slammer virus, which affects Microsoft SQL, then you simply need to get the appropriate  patches installed on your systems to protect against this vulnerability. Having a firewall and anti-virus software is not enough, you need to be proactively updating your systems on a regular basis to remediate vulnerabilities before they can be attacked.

The Blaster Worm

The Blaster Worm (also known as Lovsan, Lovesan or MSBlast) was a computer worm that spread on computers running the Microsoft operating systems: Windows XP and Windows 2000, during August 2003.

The Melissa virus

The Melissa virus, also known as "Mailissa", "Simpsons", "Kwyjibo", or "Kwejeebo", is a mass-mailing macro virus. As it is not a standalone program, it is not a worm first found on March 26, 1999

ILOVEYOU

ILOVEYOU, sometimes referred to as Love Letter, was a computer worm that attacked tens of millions of Windows personal computers on and after 5 May 2000[1] local time in the Philippines when it started spreading as an email message with the subject line "ILOVEYOU" and the attachment "LOVE-LETTER-FOR-YOU.txt.vbs".

The Anna Kournikova worm

A computer worm authored by the Dutch programmer Jan de Wit on February 11, 2001. It was designed to trick email users into opening a mail message purportedly containing a picture of tennis player Anna Kournikova, while actually hiding a malicious program.

The Concept virus

The name Concept virus refers to two different pieces of computer malware, each of which has acted as a proof of concept for a new method of propagation:

• WM.Concept (1995), the first macro virus to spread through Microsoft Word (though not the first macro virus per-se)
• Nimda (2001), named Concept Virus by its author, one of the first multi-vector Windows viruses.