"Barack Obama's recent speech on cybersecurity emphasised the threat posed by overseas criminals and enemy states, but these figures prove that there is a significant problem in his own back yard. If America could clean up its compromised PCs it would be a considerable benefit to everyone around the world who uses the net", said Graham Cluley, senior technology consultant for Sophos. "All web users need to properly defend their computers from attack, and pledge to never act upon spam messages."

Former ‘spam super-power’ Russia, however, is continuing to fall down the rankings with a current ninth position in the chart with 3.2% of global spam messages. Last year, Russia came second being responsible 7.5% of all spam – only beaten by the USA.

Poland has seen the biggest single increase in spam output since the last quarter moving up from 10th to sixth place in this global ‘hall of shame’, with the country now responsible for relaying 4.2% of all the world’s spam messages, Sophos said.

Colombia is the only nation to have left the ‘Dirty Dozen’ spammers since Q1 2009, being replaced by Vietnam this quarter.

The top twelve countries responsible for relaying spam across the globe between April and June 2009 were:

1. United States 15.6%
2. Brazil 11.1%
3. Turkey 5.2%
4. India 5.0%
5. South Korea 4.7%
6. Poland 4.2%
7. China (incl. Hong Kong) 4.1%
8. Spain 3.4%
9. Russia 3.2%
10. Italy 2.8%
11. Argentina 2.5%
12. Vietnam 2.3%
13. Other 35.9%

Spam by continent

By continent, Asia continues to be the biggest spam email offender. Almost a third of spam messages originated in the region in Q2, with South Korea and China being the biggest contributors:

1. Asia 31.7%
2. Europe 27.1%
3. South America 19.4%
4. North America 18.8%
5. Africa 2.0%
6. Oceania 0.6%
7. Other 0.4%

Hackers exploit short URLs

With the growth in the use of shortened URL services such as TinyURL, bit.ly and is.gd promoted by booming social networking, hackers have been given a new tool to lead victims to obscure links to offensive material or malicious websites in spam emails, on Twitter and/or other networks.