The American website "Techweb" recently ranked the 10 most destructive computer viruses in the past 20 years:

1. CIH (1998)

The The computer virus belongs to the W32 family and infects viable files with the **E suffix in Window* 95/98. It is extremely destructive and can rewrite the BIOS to render it useless (as long as the computer's microprocessor is Pentium Intel 430TX). The consequence is that the user's computer cannot boot. The only solution is to replace the system's original chip ( chip), a computer virus that broke out on April 26 and can also destroy all information on a computer's hard drive. This computer virus does not affect MS/DOS, Windows 3.x and Windows NT operating systems.

CIH can be spread through all possible means: floppy disks, CD-ROMs, Internet, FTP downloads, emails, etc. It is recognized as one of the most dangerous and destructive computer viruses of all time. It broke out in Taiwan, China, in June 1998, causing losses of US$20 million to US$80 million worldwide.

2. Melissa (1999)

This virus specifically targets Microsoft's email server and email sending and receiving software. It is hidden in a Word97 format file. It spreads through e-mails as attachments and is good at invading computers with Word97 or Word2000 installed. It can attack the registrar of Word97 and modify its security settings to prevent macro viruses, making the macro virus warning function of the files it infects ineffective.

In just a few hours after the Melissa virus was discovered, the virus infected millions of computers and tens of thousands of servers around the world through the Internet, and the Internet was paralyzed in many places. The outbreak broke out on March 26, 1999, infecting 15%-20% of commercial PCs and causing global losses of US$300 million to US$600 million.

3. I love you (2000)

It broke out in Hong Kong, China on May 3, 2000. It was a virus written in VBScript and could be spread through E-mail. The infected computer platforms are mainly Win95/98/2000. It has caused losses of US$10 billion to US$15 billion to the world.

4. Code Red (Code Red, 2001)

The virus can spread rapidly and cause widespread access slowdown or even blockage. This kind of virus usually first attacks the server of the computer network. The attacked server will follow the instructions of the virus to send a large amount of data to the government website, eventually causing the website to be paralyzed. The damage it causes is mainly to modify web pages, and there are indications that this worm has the ability to modify files. It broke out on July 13, 2001, causing global losses of US$2.6 billion.

5. SQL Slammer (2003)

This virus exploits the buffer overflow vulnerability of SQL SERVER 2000's parsing port 1434 to attack its service. The outbreak broke out on January 25, 2003, and 500,000 servers around the world were attacked, but the economic losses were relatively small.

6. Blaster (2003)

When the virus is running, it will constantly use IP scanning technology to find computers with Win2K or XP systems on the network. Once found, it will use The DCOM RPC buffer vulnerability attacks the system. Once the attack is successful, the virus body will be transmitted to the other party's computer for infection, causing the system to operate abnormally, restart continuously, and even cause the system to crash. In addition, the virus will also perform a denial-of-service attack on a Microsoft upgrade website, causing the website to be blocked and preventing users from upgrading their systems through the website. It broke out in the summer of 2003, and hundreds of thousands of computers were infected, causing global losses of US$2 billion to US$10 billion.

7. Sobig.F (Sobig.F, 2003)

Sobig.f is a virus that uses the Internet to spread. When its program is executed, it will E-mails itself to all the email addresses it finds on the infected computer. After being executed, the Sobig.f virus e-mails itself as an attachment to all e-mail addresses it finds on the infected computer. It uses its own SMTP engine to set up the messages it sends. The directory of this worm in the infected system is C:\WINNT\WINPPR32.EXE. The outbreak on August 19, 2003 was a variant of Sobig, causing global losses of US$5 billion to US$10 billion.

8. Bagle Fever (Bagle, 2004)

The virus spreads through email. After running, it generates a copy of itself in the system directory and modifies the registry key value. . The virus also has backdoor capabilities. It broke out on January 18, 2004, causing tens of millions of dollars in losses to the world.

9. MyDoom (2004)

MyDoom is a virus spread through email attachments and the P2P network Kazaa. When the user opens and runs the virus program in the attachment, the virus It will target the email address in the user's mailbox, forge the source address of the email, send a large number of emails with virus attachments, and leave a backdoor on the user's host that can upload and execute arbitrary code (TCP 3127< /p>

to the range of 3198). It broke out on January 26, 2004, causing network loading times to be more than 50% slower during peak periods.

10. Sasser (2004)

This virus is a worm that exploits the Lsass buffer overflow vulnerability (MS04-011 vulnerability information) of the Microsoft operating system to spread. Since the worm will initiate a large number of scans during its propagation process, it will have a great impact on individual users and network operations. It broke out on April 30, 2004, causing tens of millions of dollars in losses to the world.