The United States continues to host more malware and botnets than any other country, including Russia and China, which are often viewed as the biggest sources for cybercrime campaigns worldwide.

According to IBM’s latest X-Force Threat Intelligence Quarterly, roughly one-quarter of all command-and-control (C&C) servers that are used to control botnets globally and more than 40 percent of sites serving malware are hosted in the U.S.

The number of sites hosted in the U.S. serving malware is nearly four times greater than second-place China, which hosts around 11 percent of all malicious links worldwide, and about five times greater than Germany, which is in third place with 8.3 percent.

These statistics are a sobering reminder that more malware attacks originate closer to home than originally assumed. However, they do not tell the whole story on malware and botnets.

Malware and Botnets in the US

When the number of malicious sites and servers in a country are considered as a percentage of the total number of IP-addressable systems in that country, the U.S. drops dramatically down the list of the top nations for hosting malware.

In fact, it doesn’t even show up on the list of the top 20 offenders for hosting malware and botnets. When the numbers are normalized, Hong Kong emerges as the leader for hosting malicious sites, with a somewhat startling infection rate of 11 percent of all installed systems. It is followed by Lithuania and Bulgaria, with about a 10 percent contamination rate each.

Similarly, the U.S. drops out of the list of top nations for hosting C&C servers when the number of malicious systems is taken as a percentage of all installed systems in the country. Lithuania tops the list of nations hosting the largest number of C&Cs, followed by a slew of Eastern European nations, including Belarus, Slovakia and the Ukraine.

What the raw numbers do not indicate is whether the sites and servers hosting malicious content were set up for that specific purpose or whether they were legitimate sites that were compromised, the IBM report noted.

X-Force Threat Intelligence Quarterly

IBM’s X-Force Threat Intelligence report provides a quarterly overview of the major security trends for the preceding three months.

The statistics in the report provide an important indicator of the threats enterprises face from malicious systems hosted in other countries, according to Chris Poulin, research strategist at IBM and one of the authors of the report.

One of the goals of the quarterly threat intelligence report is to arm enterprises with information about what they should look for on the threat landscape, he said.

“For example, if you look at where command-and-control servers are located, one of the things organizations can do is start creating correlation rules that look for access to those particular countries,” he said.

The reason why the United States has consistently topped the list of countries hosting malware sites is simply because it also has the largest base of installed systems, Poulin said. Therefore, instead of looking at just the raw, absolute numbers, IBM decided to look at the percentage of the total number of systems in a particular country, he said. This approach shows that a disproportionately large number of malicious sites and servers are hosted in Eastern Europe.

IBM’s report is the latest to highlight the global scope of malware attacks these days. Earlier this year, researchers at security vendor FireEye identified C&C servers hosted in as many as 206 countries worldwide. That number was notably higher than the 184 countries where such servers were located just one year ago.

On average, enterprises are attacked once every 1.5 seconds by malware hosted on such systems, FireEye noted in its report.