Inktomi to check viruses at cache

The company hopes the deal will block a relatively new path that viruses have into corporate networks: Web pages.

"We can assure that any content a user requests from the Web is clean," said Liz Padula, market development manager for the Foster City, Calif., company.

The software will scan any object from a Web site for malicious code before caching that object to Inktomi's Traffic Edge Security Edition server software, which serves pages to employees' browsers and also saves pages for easy recall. By only caching clean content, and not potential viruses, the antivirus software can prevent malicious code from finding its way into a company from a traditionally unmonitored source.

"It is yet another way for viruses to get in," said Steve Trilling, director of Symantec Security Response. "Nimda is a perfect example of something that spread through a Web site mechanism."

Nimda would infect vulnerable Web sites, appending JavaScript that caused a victim's browser to download the actual virus. Normally, viruses that spread using the Web are easily defanged by simply shutting down infected sites. However, theoretically, the viruses could continue to "live" beyond the shutdown in a company's caching server.

While worms spreading via Web sites are relatively rare--far more common are worms that use e-mail and software exploits--many times a worm can bypass a company's protections against the more major vectors by taking to the Web, said Trilling.

"I think you need to consider any potential network connection as a way to transmit viruses," Trilling said.