Well-known viruses include: Stuxnet, Duqu, Flame, Wiper, I Love You, code red, NIMDA, Heartbleed, Shellshock
A software program that replicates on computer systems by incorporating itself into shared programs. Viruses range from harmless pranks that merely display an annoying message to programs that can destroy files or disable a computer altogether. Whether they're considered malicious or malevolent, all viruses spread rapidly. For example, from one computer to millions of others around the world, infecting machines and causing them to crash.
Viruses are most commonly transmitted through e-mail ("strains" have appeared that use personal e-mail address books to propagate themselves from machine to machine) but are also transmitted through backdoors. If you are connected to the Internet or any other network, it is important that you take precautions against viruses. Get a virus-scanning program and do not open any e-mail attachments from people you do not know.
One tech support woman told me, "It may sound silly but get in the habit of scanning your computer from your anti-virus software's Web site because sometimes malware can hide but if you do it from their Web site it can't hide."
VIRUS TIP: To avoid spreading computer viruses via e-mail, create a contact in your e-mail address book with the name !0000 (an exclamation mark and four zeros) and no e-mail address in the details. This contact will then show up as your first contact. If a virus attempts to do a "send all" to your contact list, your computer will put up an error message saying, "The message could not be sent. One or more recipients do not have an e-mail address. Please check your address book and make sure all the recipients have a valid e-mail address." The offending message (with the virus) may then be automatically stored in your Drafts or Outbox folder. Go in there and delete the offending message. (This is not a substitute for virus protection software, and it will not protect you from getting a virus, but it will prevent your computer from sending the virus to everyone on your contact list. Note: This trick may not work on all email programs.)
Historical perspective: According to a security report released in 2012, a complex computer virus has been pilfering confidential information from computers in the Middle East for at least two years. The virus, called Flame, has been infecting computers in Iran, Israel, Lebanon, Sudan, Syria, Saudi Arabia and Egypt. It has been grabbing images of users' computer screens, recording their instant messaging chats, remotely turning on their microphones to record their audio conversations and monitoring their keystrokes and network traffic, according to a report by Kaspersky Labs, a Moscow-based security research firm.
If the report's findings prove to be true, Flame would be the third major Internet weapon to have been discovered since 2010. The first, named Stuxnet, was intended to attack software in specialized industrial equipment, and was used to destroy centrifuges in an Iranian nuclear facility in 2010. The second virus, called Duqu, like Flame, performed reconnaissance. Security researchers believe Duqu was created by the same group of programmers behind Stuxnet.The researchers said Flame appeared to have been developed by a different group of programmers. It contains 20 times more code than Stuxnet and is much more widespread than Duqu. Researchers believe Duqu hit fewer than 50 targets worldwide.
Kaspersky's researchers said they had detected Flame on thousands of computers belonging to individuals, private companies and universities across the Middle East. "Flame can easily be described as one of the most complex threats ever discovered," said Alexander Gostev, the head of Kaspersky's Global Research and Analysis team. "It's big and incredibly sophisticated. It pretty much redefines the notion of cyberwar and cyberespionage." Researchers say they do not know who is behind the virus, but given its complexity and the geography of its targets, they said it was most likely being staged by a government.
The authors of Stuxnet and Duqu are also unknown but their targets and digital evidence suggest to some researchers that they may have been part of a joint American-Israeli project to sabotage Iran's nuclear program. Kaspersky's researchers said the majority of computers infected with Flame were located in Iran. Like Duqu and Stuxnet, Flame infects machines through a known security hole in the Windows operating software. Researchers discovered Flame while investigating reports that another computer virus, called Wiper, had been erasing computer programs in Iran. The International Telecommunications Union, a United Nations agency, had asked Kaspersky's researchers to look into Wiper when they discovered that thousands more computers had been infected with Flame.
Do Macs get viruses? Yes, but not nearly as much... read the NetLingo blog "One in Five Macs have Malware." For more info on viruses, click on the "more info" button below!