According to a report (PDF) released by Panda Security, computer trojans accounted for almost 52% of new malware created in the past three months. Meanwhile, the number of traditional virus samples received by the antivirus vendor during the last quarter has almost doubled.

Computer trojans remain the malware type most preferred by cybercriminals. This is no surprise, considering that threats like Zbot or Clampi, which were used to steal millions of dollars from users and companies in the past year alone, fall in this category. Additionally, most of today's spam is generated by trojan-infected computers, which are controlled en mass as botnets.

Panda reports that 51.78% of new malware samples it analyzed in the second quarter of 2010 were trojans. As far as distribution go, the number of infections with this type of malware accounted for 53,14% of the total registered during the same period.

The antivirus vendor points out that a spike in the number of traditional virus samples has also been recorded. Viruses “totaled just over 24.35%. Comparing this figure with the previous quarter (15.13%), it is clear that viruses continue to gain ground,” the Panda researchers say. However, this spectacular growth is not also reflected in the number of new infections, where viruses represent only 13,42% of the total.

When it comes to regional distribution, Taiwan was the most troubled country, with at least one infection present on over half of scanned computers. Russia also came close with a bit under 50%, while Turkey completes the top 3 with around 45%. Another interesting aspect is that first 15 countries on this list all registered rate of over 30%, meaning that one in three computers was infected.

Meanwhile, Brazil takes the lead in the top of most spamming countries, accounting for around 10% of all registered spam. India with a bit over 8% and Russia with around 6% follow. The United States is in the 5th position, being responsible for around 5% of the world's junk mail traffic during the last three months.

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