The Web site of BusinessWeek magazine suffered a major SQL injection attack in recent days that left it hosting malware on hundreds of its pages, security vendor Sophos PLC has reported.

Once compromised by such a server hole, the attack scripts could, in principle, launch anything desired by the attacker except currently included code for automatic attacks based on JavaScript. That means a visitor could be hit by malware just by landing on one of the pages, without even interacting in any way.

Luckily, according to Sophos, the code that's still on the magazine site pointed to a Russian site that appeared to be nonfunctioning -- although leaving the code in place meant it could be reactivated at any time.

"BusinessWeek needs to get rid of these hundreds of pieces of malicious script as soon as possible, before a hacker puts malware up which would be activated by them," said senior technology consultant Graham Cluley at Sophos.

The compromised part of the site is used by the magazine to advertise jobs to MBA graduates.

"BusinessWeek and the many other firms hit by SQL injection attacks need to move fast to not only remove the malicious scripts, but also to ensure that they do not get infected again. Companies whose Web sites have been struck by such an attack often clean up their database only to be infected again a few hours later," said Cluley.

Sophos has posted a video on its site that runs through the BusinessWeek attack in more detail. In the video, Cluley points out that the attackers wouldn't have needed to target BusinessWeek specifically to have found the vulnerability from which the attacks sprang -- a search engine could have been used to hunt down the vulnerable code.

Sophos is now finding 16,000 new malicious Web pages every day, 90% of which were being hosted from legitimate sites, he said.

A similar attack was used earlier in 2008 to undermine 500,000 legitimate Web sites in a period of days.