In the first six months of 2008, one webpage was infected every five seconds, Sophos said in its Security Threat report.
This was worse than in the figure in 2007, when one infected webpage was found every 14 seconds. The 2008 figure meant that Sophos found 16,173 malicious webpages every day, with 90 per cent being on legitimate sites which had been the victim of hacking.
The report said that SQL injections had been one of dominant malware trends in the first six months of 2008, according to Sophos. The attacks exploit security vulnerabilities and insert malicious code (script tags) into a database which runs a website.
"There's been a concerted campaign to infect people," said Sophos senior technology consultant Graham Cluley. "If you were to paint a picture of what the first six months of 2008 were all about when it came to malware, it was about SQL injections hitting websites."
Cluley said this was becoming the trend for malware rather than attachment on emails which were usually filtered before getting to the user. He also said that it was also popular because legitimate sites which were already getting traffic were getting hit.
"It is easy using Google to find vulnerable webpages," he said. "It is easy to find websites which haven't been constructed properly, and to inject your code. It's relatively trivial to do, but really effective."
Cluley said that web development teams could look at code and harden it, but smaller companies were not usually able to do it. However he said that there were tools available from companies like Microsoft and HP which would look at code and attempt to find and warn about vulnerabilities.
He said that website attacks such as SQL injections would only increase in the next six months: "There are many companies out there who haven't done enough to defend their websites. They need to start scanning users' web access as well as their emails."
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