It's a threat that worries many companies, so much so that "zero-day defenses" has become a buzzword for the industry and new companies have sprung up to meet the need for new technology.

One such company, network security firm CounterStorm, has found that security managers are eager to find solutions to the zero-day issue.

"We have yet to meet the chief information security officer who is not worried about zero-day attacks and companies are freeing up the budget to deal with the problems," CounterStorm CEO Gil Arbel said in a recent interview.

Other companies see zero-day defenses as a way to free themselves from the chaos of emergency patches. A major benefit of deploying security technologies to defend against zero-day attacks is that firms can patch on a regular schedule. Continental Airlines, a client of eEye, has moved from patching multiple times a month to once a quarter, said Andre Gold, the director of information security for Continental.

Reducing the amount of time spent patching is as much a benefit as protecting against zero-day attacks, Gold said. Patching is not a security activity, but a system administration activity--playing continual catch-up with the legion of black-hat attackers is not good security, Gold said. Even Microsoft's monthly patches are too frequent for the company, he said.

"The ad hoc scenario kept us in chaos around here," Gold said. "The monthly frequency allows us to schedule resources, but that is still too frequent for us because it does not allow us to do regression testing."

Zero-day attacks will not go away, according to Tom Liston, a handler with the SANS Institute, an education and training organization. Liston had recommended that people deploy the unofficial patch from Guilfanov as an emergency measure.

No operating system will be free from flaws, but the fact that Microsoft has to retain potentially insecure code to support backwards compatibility makes it more likely that the security community may face a similar situation to the vulnerability in the Windows Meta File format, he said.

"The whole issue here is caused by backwards compatibility issues," Liston said. "Not only does Microsoft have to support code for Windows, but also code that goes back 15 years and that is not going to change."