U.S. suffers the worst for Spam

The US has failed to make inroads into its spam-relaying problem, according to figures from security vendor Sophos.

Spam messages received in the company's global network of spam traps, have revealed that for the first time in more than two years, the US has not reduced spam in the last quarter.

Graham Cluley, senior technology consultant at Sophos, said: 'Since the introduction of the CAN-SPAM legislation in 2004, we've seen a regular quarter-on-quarter drop in the proportion of spam coming from the US - until now, that is.

'Given the number of arrests, and the huge fines dished out to guilty spammers, it's hard to criticise the US for failing to take action. Perhaps the reality is that the statistics can't be reduced any further unless US home users take action to secure their computers and put a halt to the zombie PC problem.'

The US remains stuck at the top of the chart and is the source of 23.2 per cent of the world's spam. Its closest rivals are China and South Korea, although both of these nations have managed to reduce their statistics since the first quarter of 2006.

The vast majority of this spam is relayed by botnets.

Asia accounts for more spam than any other continent, however spam relaying in Europe continues to become more prevalent. Europe has now overtaken North America as the second largest spreader of spam.

Sophos estimates that 15 per cent of all spam emails are now pump-and-dump scams, compared to just 0.8 per cent in January 2005. These are email campaigns designed to boost the value of a company's stock in order for spammers to make a quick profit. Many of these spam messages contain images rather than traditional text.

'The people that act upon these emails aren't skilled investors, and don't r ealise that purchasing the shares is likely to reap no reward, benefiting only the spammers, while creating a financial rollercoaster for the organisation in question,' said Cluley.

Spam containing embedded images has risen sharply from 18.2 per cent in January to 35.9 per cent in June. By using images instead of text, messages are able to avoid detection by some anti-spam filters that rely on the analysis of textual spam content.