Well, this is a notification, and a donation from myself to GP, to make them alert about the internal threts. Here are most destructable virusus, which you are going to look at, but not take it, obviously
1 : ILOVEYOU a.k.a. Lovebug/ Loveletter Virus
The ILOVEYOU virus was a computer virus that many consider to be the most damaging virus ever written. It spread itself by email in 2000 through an attachment in the message. Once opened, it loaded itself to the memory, infecting executable files. When a user received and opened the email containing the attachment “LOVE-LETTER-FOR-YOU.txt.vbs”, the computer became automatically infected. It then spread itself by infecting executable files, image files, as well as audio files like MP3s. After that, the virus sent itself to others by looking up the addresses contained in the MS Outlook contact list. The virus was written by a Filipino programmer who was still a college student at that time. He said the release of the virus was only “accidental.” This virus spread throughout the world in just a day, infecting computers of large corporations and governments, including the Pentagon in the United States. It caused billions of dollars in damages. The actual “damage” occurred during the removal of the infection from computers, as email servers and computer networks had to be shut down before the virus could be removed.
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2 : CIH a.k.a. Chernobyl Virus
This virus was considered one of the most dangerous and most destructive viruses ever because it had the ability to remain undetected in a computer’s memory, infecting every application that was run. First released in 1998, the CIH virus infected executable files of the operating systems Windows 95, 98, and ME. This virus also was accidentally distributed by a software vendor, contributing to the massive infection of computers. What made this virus dangerous was that it had a trigger date. Once that date was reached, it overwrote the files on the hard drive and completely destroyed its contents. It also had the ability to overwrite the BIOS of the computer to prevent it from booting up. This virus was also known as the Chernobyl virus because some variants were set to destroy data in computers that coincided with the Nuclear Powerplant accident
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3 : Melissa Virus
Released in 1999, the Melissa virus was another mass-mailing malware that was said to have infected up to 20 percent of computers worldwide. This included the networks of Microsoft, Intel, and other companies that relied on MS Outlook as their email client. Email servers around the world were forced to shut down in order to prevent the virus from spreading, as well as to remove the virus from their system. The virus came through email including an MS Word attachment. When opened, it emailed itself to the first 50 people in the MS Outlook contact list. It also overwrote the document files in the infected computer with quotes from the famous cartoon TV series “The Simpsons.”
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4 : Code Red
The world had not yet recovered from the damage caused by the ILOVEYOU virus when Code Red was released in mid-2001. Unlike other viruses, this one only targeted certain computers running the Microsoft IIS (Internet Information Server) Web Server, exploiting a bug in the software. Once a computer was compromised by the virus, it would modify the handled website, displaying the message “Welcome to h t t p ://w w w . w o r m . c o m! Hacked by Chinese!” (In the original, it dosen't have those spaces) Then, it would later seek other computers running the web server software and do the same thing. After about two weeks of infection, the virus was programmed to launch DDoS (Distributed Denial of Service) attacks on certain websites, including the server of the White House.
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5 : Bagle
Bagle was another classic type of mass-mailing malware, but was quite complex. First detected in 2004, it infected users through an email attachment, and also used email to spread itself. Unlike previous mass-mailing viruses, Bagle did not rely on the MS Outlook contact list to make a list of where to send itself. It harvested email addresses from various document files stored in the infected computer – from plain-text files to MS Excel files. The danger of this virus was that its design opened a backdoor where a remote user – probably the author or a group of hackers - could gain access and control of the infected computer. It could download additional components to either spy and steal information from the user or launch DDoS attacks to certain networks and computers. Though the original Bagle virus was designed to stop spreading after January 2004, hundreds of variants today are still out there, spreading.
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Source & Read upto Top 10 : http://crunkish.com/top-ten-worst-computer-viruses/
1 : ILOVEYOU a.k.a. Lovebug/ Loveletter Virus
The ILOVEYOU virus was a computer virus that many consider to be the most damaging virus ever written. It spread itself by email in 2000 through an attachment in the message. Once opened, it loaded itself to the memory, infecting executable files. When a user received and opened the email containing the attachment “LOVE-LETTER-FOR-YOU.txt.vbs”, the computer became automatically infected. It then spread itself by infecting executable files, image files, as well as audio files like MP3s. After that, the virus sent itself to others by looking up the addresses contained in the MS Outlook contact list. The virus was written by a Filipino programmer who was still a college student at that time. He said the release of the virus was only “accidental.” This virus spread throughout the world in just a day, infecting computers of large corporations and governments, including the Pentagon in the United States. It caused billions of dollars in damages. The actual “damage” occurred during the removal of the infection from computers, as email servers and computer networks had to be shut down before the virus could be removed.
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2 : CIH a.k.a. Chernobyl Virus
This virus was considered one of the most dangerous and most destructive viruses ever because it had the ability to remain undetected in a computer’s memory, infecting every application that was run. First released in 1998, the CIH virus infected executable files of the operating systems Windows 95, 98, and ME. This virus also was accidentally distributed by a software vendor, contributing to the massive infection of computers. What made this virus dangerous was that it had a trigger date. Once that date was reached, it overwrote the files on the hard drive and completely destroyed its contents. It also had the ability to overwrite the BIOS of the computer to prevent it from booting up. This virus was also known as the Chernobyl virus because some variants were set to destroy data in computers that coincided with the Nuclear Powerplant accident
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3 : Melissa Virus
Released in 1999, the Melissa virus was another mass-mailing malware that was said to have infected up to 20 percent of computers worldwide. This included the networks of Microsoft, Intel, and other companies that relied on MS Outlook as their email client. Email servers around the world were forced to shut down in order to prevent the virus from spreading, as well as to remove the virus from their system. The virus came through email including an MS Word attachment. When opened, it emailed itself to the first 50 people in the MS Outlook contact list. It also overwrote the document files in the infected computer with quotes from the famous cartoon TV series “The Simpsons.”
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4 : Code Red
The world had not yet recovered from the damage caused by the ILOVEYOU virus when Code Red was released in mid-2001. Unlike other viruses, this one only targeted certain computers running the Microsoft IIS (Internet Information Server) Web Server, exploiting a bug in the software. Once a computer was compromised by the virus, it would modify the handled website, displaying the message “Welcome to h t t p ://w w w . w o r m . c o m! Hacked by Chinese!” (In the original, it dosen't have those spaces) Then, it would later seek other computers running the web server software and do the same thing. After about two weeks of infection, the virus was programmed to launch DDoS (Distributed Denial of Service) attacks on certain websites, including the server of the White House.
--
5 : Bagle
Bagle was another classic type of mass-mailing malware, but was quite complex. First detected in 2004, it infected users through an email attachment, and also used email to spread itself. Unlike previous mass-mailing viruses, Bagle did not rely on the MS Outlook contact list to make a list of where to send itself. It harvested email addresses from various document files stored in the infected computer – from plain-text files to MS Excel files. The danger of this virus was that its design opened a backdoor where a remote user – probably the author or a group of hackers - could gain access and control of the infected computer. It could download additional components to either spy and steal information from the user or launch DDoS attacks to certain networks and computers. Though the original Bagle virus was designed to stop spreading after January 2004, hundreds of variants today are still out there, spreading.
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Source & Read upto Top 10 : http://crunkish.com/top-ten-worst-computer-viruses/