Security vendor <A HREF="http://www.cio.com/article/196656/Trend_Micro_Hit_By_Massive_Web_Hack">Trend Micro has fallen victim to a widespread Web attack</A> that splashed malicious software onto hundreds of legitimate Web sites in recent days.

A Trend Micro spokesman confirmed that the company's site had been hacked Thursday, saying that the attack took place earlier in the week. "A portion of our site--some pages were attacked," said Mike Sweeny, a Trend Micro spokesman. "We took the pages down overnight Tuesday night--and took corrective action."

On Thursday security vendor McAfee reported that more than 20,000 Web pages have been affected by the attack. The pages are infected with malicious code that tries to install password-stealing software on the PCs of people who visit the sites.