The yearly reported number of virus for 2008 was 21,591: drastically decreased from 34,334 reported in 2007.  Resulted in 54,174 in 2005, the reported number of virus was continually decreased thereafter.  Since massive mail distribution type of virus which causes large infection had not emerged over the past 5 years, it can be assumed that the reported number itself was decreased.

Chart 1-1: Reported Number of Virus/Year

The reported virus was 136 (2007: 166): of the virus newly reported in 2008 was 19 (2007: 46).

The worst reported number of virus was W32/Netsky and W32/Autorun and W32/Mytob respectively were, too, the frequently detected/reported viruses.  W32/Netsky was the most reported virus every year since 2004.  In addition, W32/Autorun is the virus which enlarges infection via USB memory and was drastically increased in October 2008 (See the Chart 2-1).

According to the shift in detected number classified by virus, W32/Netsky was continually taking over the largest part of the report.  However, in September 2008, W32/Autorun was started to increase so that the detection number was, drastically increased the following month, in October.  Though it was decreased in December, it can be said that USB memory infection type of virus was drastically spread over, but temporarily.

Chart 2-1: Detection Number of Virus by Month

According to the reported number classified by virus, though the reported number was tending to decrease, but W32/Netsky is still reported the most. Many of the other viruses, too, were shifted maintaining same level: Since the reported number of W32/Autorun was tending to increase, the reported number of W32/Netsky was followed by that in October 2008.

Chart 2-2: Reported Number Classified by Virus

Information-Technology Promotion Agency, Security Center
Hanamura/Kagaya/Ooura
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