Google has been looking into web-based malware and has come up with some worrying figures. Of the 4.5m web pages it looked at in depth, 450,000 were capable of downloading malicious code without the user's knowledge.
A further 700,000 web pages in Google's study contained code which could potentially compromise a user's computer.
The research, titled 'The Ghost in the Browser', found that the vast majority of malicious web pages exploit vulnerabilities in Internet Explorer.
Google has already started to identify web pages that could potentially be malicious and flag them up for searchers:
"Our goal is to observe the malware behavior when visiting malicious URLs and discover if malware binaries are being downloaded as a result of visiting a URL.
"Websites that have been identified as malicious are labeled as potentially harmful when returned as a search result."
Google also made the point that the rise of Web 2.0 and user generated content has given attackers more scope to attack internet users' PCs.
Malware threat doubles over last year