In simple terms, a virus can aptly be called a virtual disease which affects a computer system and makes it sick, forcing to act in a manner undesired by the user., There are billions of viruses out there, big and small. But there were some that stood out and ruined things for us in a spectacular fashion. Almost 10 years ago the number 1 virus that shock the world was created. Below is a list of 10 of the deadliest virus which create havoc in the virtual as well as the real world.
| 10. Sasser (2004) Sasser was at first believed to have been authored in Russia by the same person(s) who created another worm usually referred to as Lovsan, MSBlast or Blaster (due to the media), a connection indicated by code similarities between the two, but on May 7, 2004, 18-year old German computer science student Sven Jaschan from Rotenburg, Lower Saxony was arrested for writing the worm. |
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| 9. Morris How big is the Internet, you ask? In 1988, Cornell University student named Robert Tappan Morris launched 99 lines of code in his quest for the answer. While his intentions were not malicious, there were bugs in his code that caused affected hosts to encounter a plethora of stability problems that effectively made these systems unusable. The result was increased load averages on over 6,000 UNIX machines across the country which caused between $10,000,000 and $100,000,000 of damage. |
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| 8. Conficker (2009) The Conficker worm has created a secure, worldwide infrastructure for cybercrime. The worm allows its creators to remotely install software on infected machines. What will that software do? We don't know. Most likely the worm will be used to create a botnet that will be rented out to criminals who want to send SPAM, steal IDs and direct users to online scams and phishing sites. |
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| 7. Code Red (2001) 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 http://www.worm.com! Hacked by Chinese!” 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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| 6. CIH (1998) CIH, also known as Chernobyl or Spacefiller, is a computer virus written by Chen Ing Hau of Taiwan. It is considered to be one of the most harmful widely circulated viruses, overwriting critical information on infected system drives, and more importantly, in some cases corrupting the system BIOS. The name "Chernobyl Virus" was coined some time after the virus was already well-known as CIH, and refers to the complete coincidence of the payload trigger date in some variants of the virus (actually the virus writer's birthday) and the Chernobyl accident, which happened in Ukraine on April 26, 1986. Today, CIH is not as widespread as it once was, due to awareness of the threat and the fact it only affects older Windows 9x (95, 98, Me) operating systems. The virus made another comeback in 2001 when a variant of the Loveletter Worm in a VBS file that contained a dropper routine for the CIH virus was circulated around the internet, under the guise of a nude picture of Jennifer Lopez. |
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| 5. Sobig Worm (2003) The Sobig Worm was a computer worm that infected millions of Internet-connected, Microsoft Windows computers in August 2003. It was written using the Microsoft Visual C++ compiler, and subsequently compressed using a data compression program called tElock. There are plenty of variants of the Sobig worm, but the most destructive and widespread of all is called Sobig.F. Sobig is a computer worm in the sense that it replicates by itself, but also a Trojan horse in that it masquerades as something other than malware. The Sobig worm will appear as an electronic mail and will contain the text: "See the attached file for details" or "Please see the attached file for details." .The Sobig.F worm deactivated itself on September 10, 2003. On November 5 the same year, Microsoft announced that they will pay $250,000 for information leading to the arrest of the creator of the Sobig worm. To date, the perpetrator has not been caught. |
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| 4. Blaster (2003) The Blaster Worm (also known as Lovsan or Lovesan) was a computer worm that spread on computers running the Microsoft operating systems, Windows XP and Windows 2000. The worm was first noticed and started spreading on August 11, 2003. The rate that it spread increased until the number of infections peaked on August 13, 2003. Filtering by ISPs and widespread publicity about the worm curbed the spread of Blaster. The worm was programmed to start a SYN flood on August 15, 2003 against port 80 of windowsupdate.com, thereby creating a distributed denial of service attack (DDoS) against the site. The damage to Microsoft was minimal as the site targeted was windowsupdate.com instead of windowsupdate.microsoft.com to which it was redirected. Microsoft temporarily shut down the targeted site to minimize potential effects from the worm. Although the worm can only spread on systems running Windows 2000 or Windows XP (32 bit) it can cause instability in the RPC service on systems running Windows NT, Windows XP (64 bit), and Windows Server 2003. If the worm detects a connection to the Internet (regardless of dial-up or broadband), this can even lead to the system becoming so unstable that it displays the following message and then restarts (usually after 60 seconds). The worm contains two messages hidden in strings. The first: I just want to say LOVE YOU SAN!! This is why the worm is sometimes called the Lovesan worm. The second: billy gates why do you make this possible ? Stop making money and fix your software!! It is a message to Bill Gates, Microsoft co-founder. |
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| 3. Melissa (1999) The Melissa worm, also known as "Mailissa", "Simpsons", "Kwyjibo", or "Kwejeebo", is a mass-mailing macro virus, hence leading some to classify it as a computer worm. First found on March 26, 1999, Melissa shut down Internet mail systems that got clogged with infected e-mails propagating from the worm. Melissa was not originally designed for harm, but it overflowed servers and caused unplanned problems. Melissa can spread on word processors Microsoft Word 97 and Word 2000. It can mass-mail itself from e-mail client Microsoft Outlook 97 or Outlook 98. The worm does not work on any other versions of Word, including Word 95, Microsoft Office Word 2003, Word 2004 (Mac), and Microsoft Office Word 2007, nor can it mass-mail itself via any other e-mail client, even Outlook Express or Windows Mail (Outlook Express version in Windows Vista). Melissa was first distributed in the Usenet discussion group alt.sex. The virus was inside a file called "List.DOC", which contained passwords that allow access into 80 pornographic websites. The worm's original form was sent via e-mail to many people. |
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| 2. Mydoom (2004) Mydoom, also known as W32.MyDoom@mm, Novarg, Mimail.R and Shimgapi, is a computer virus affecting Microsoft Windows. It was first sighted on January 26, 2004 and became the fastest-spreading e-mail worm ever, exceeding previous records set by the Sobig worm. Mydoom is primarily transmitted via e-mail, appearing as a transmission error, with subject lines including “Error”, “Mail Delivery System”, “Test” or “Mail Transaction Failed” in different languages, including English and French. The mail contains an attachment that, if executed, resends the worm to e-mail addresses found in local files such as a user's address book. It also copies itself to the “shared folder” of peer-to-peer file-sharing application KaZaA in an attempt to spread that way. Mydoom appears to have been commissioned by e-mail spammers so as to send junk e-mail through infected computers. The worm contains the text message “andy; I'm just doing my job, nothing personal, sorry,” leading many to believe that the worm's creator was paid to do so. Early on, several security firms published their belief that the worm originated from a professional underground programmer in Russia. The actual author of the worm is unknown |
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| 1. ILOVEYOU(2000) Almost 10 years ago the number 1 virus that shock the world was created, the ILOVEYOU worm (a.k.a. VBS/Loveletter and Love Bug worm), a computer worm written in VBScript, is considered by many as the most damaging worm ever. It started in the Philippines on May 4, 2000, and spread across the world in one day (traveling from Hong-Kong to Europe to the United States), infecting 10 percent of all computers connected to the Internet and causing about $5.5 billion in damage. Most of the "damage" was the labor of getting rid of the virus. The worm arrived in e-mail boxes with the simple subject of "ILOVEYOU" and an attachment "LOVE-LETTER-FOR-YOU.TXT.vbs". The Pentagon, CIA, and the British Parliament had to shut down their e-mail systems to get rid of the worm, as did most large corporations. The worm overwrote important files, as well as music, multimedia and more, with a copy of itself. It also sent the worm to everyone on a user's contact list. This particular worm only affected computers running the Microsoft Windows operating system. While any computer accessing e-mail could receive an "ILOVEYOU" e-mail, only Microsoft Windows systems would be infected. The worm propagates by sending out copies of itself to all entries in the Microsoft Outlook address book. It also has an additional component, in which it will download and execute an infected program called variously "WIN-BUGSFIX.EXE" or "Microsoftv25.exe". This is a password-stealing program which will e-mail cached passwords. The ILOVEYOU worm is believed to have been written by Burningice & Moon. The Barok trojan horse used by the worm is believed to have been written by dark_tech, a Filipino student of AMA Computer University in Makati, Philippines. Onel A. de Guzman, the creator of the virus and a resident of the Philippines, had all charges dropped against him for creating the worm because there were no laws at the time prohibiting the creation of computer worms. Since then, the government of the Philippines has laid out penalties for cybercrime that include imprisonment for 6 months to 3 years and a fine of at least 100,000 pesos (USD $2000). |
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