SecureWorks published the locations of the computers, from which the greatest number of cyber attacks were attempted against its clients in 2008. The United States topped the list with 20.6 million attempted attacks originating from computers within the country and China ran second with 7.7 million attempted attacks emanating from computers within its borders.

This was followed by Brazil with over 166,987 attempted attacks, South Korea with 162,289, Poland with 153,205, Japan with 142,346, Russia with 130,572, Taiwan with 124,997, Germany with 110,493, and Canada with 107,483.

Computer security can be greatly improved by keeping your web browser and operating system up to date, using the latest versions of antivirus and antispyware software, following safe computer practices such as being wary of the websites you visit, and not clicking on attachments and links within emails until verifying that the sender intentionally sent the enclosed link or attachment.

These findings illustrate the ineffectiveness of simply blocking incoming communications from foreign IP addresses as a way to defend your organization from cyber attacks, as many hackers hijack computers outside their borders to attack their victims. The Georgia/Russia cyber conflict was a perfect example of this. Many of the Georgian IT staff members thought that by blocking Russian IP addresses they would be able to protect their networks, however, many of the Russian attacks were actually launched from IP addresses in Turkey and the United States so consequently they were hit hard. This was a perfect example where we saw Russian cyber criminals using compromised computers outside their borders.

China's hackers do create botnets from spamming through email and blogs, but a relatively larger percentage of the compromised hosts under Chinese control are simply machines in schools, data centers, companies - in other words, on large networks - that are mostly unguarded and consequently are entirely controlled by hacker groups, as opposed to distributed bots harvested from widely distributed international spam runs. Often the groups have an insider in the networks they own. We also see many local hacker groups in Japan and Poland compromise hosts within their own country to use in cyber attacks, so the Chinese hackers are not alone in using resources within their own borders.

With hackers utilizing computer resources inside and outside of their borders, SecureWorks suggests that in addition to securing computers with ongoing system and security updates and patches, organizations should utilize a black list to block inbound communications from known malicious IP addresses.

Organizations should also block outbound communications to foreign countries known to harbor hackers and block outbound communications to hostile networks known to host criminal activity. This way if your organization does have an infected host within its network, then the host will be blocked from sending personal or company data to the cyber criminals. Of course, some of these hostile networks do support a handful of legitimate sites. In addition to a blacklist, your organization can use a separate whitelist to allow outbound communication only to trustworthy sites on those otherwise hostile networks.