The number of e-mails containing malicious software is increasing, according to recent statistics released by IT security and control firm Sophos.
In September 0.12 per cent of e-mails - or 1 in 833 - carried malicious attachments. This is up from 1 in 1000 in August. A Sophos spokesperson attributes this increase in activity to a "coordinated campaign by hackers to spam out the Pushdo Trojan horse en masse during the second half of September".
The infected e-mails claim to include nude images of Hollywood celebrities such as Angelina Jolie - but they contain attachments that, once opened, give hackers control over the infected PC.
Hackers clearly see e-mail as a viable method of attack. In one particular 24-hour period, Sophos recorded that four in five malware e-mails contained the Pushdo Trojan.
The rise in frequency of e-mail-based malware distribution serves as a reminder that individuals and businesses need to secure their inboxes and computer systems and think before opening e-mails.
"The trick of tempting users with scantily clad pictures of hot-looking girls is as old as the hills - but people still fall for it," said Carole Theriault, senior security consultant at Sophos.
Sophos also discovered 5400 Web sites hosting malicious code per day through the month of September. Over 85 per cent of infected Web sites were hosted in three countries -- China, the US or Russia. The percentage of infected sites hosted in the US has dropped in recent months, but there was a 3 per cent rise in Russian sites hosting malicious content.