Microsoft developer: 'Fuzzing' key to Office security

But nothing's perfect, says SDL guru David LeBlanc, who admits past slip-ups

Among the ways the Office team is trying to get a step on attackers, said LeBlanc, is with stepped up fuzzing. He pointed to a presentation at last month's Black Hat security conference that described using generic algorithms to cover more code during fuzzing, a technique he said Microsoft had been working on for a couple of years.

"Right now, the technique is only able to exercise relatively simple network protocols, like HTML, which is a lot simpler than a Word document," said LeBlanc. "Given five years, will attackers figure out a way to scale that? Our job is to figure out if they will so we can protect our customers for the life of the product."

Even the most diligent efforts, however, won't find every flaw, LeBlanc admitted. "One of the problems with fuzzing is it's really hard to say when you're done. Have you exercised the code sufficiently?"

A good example of something testing didn't spot during Office 2007's development -- not to mention the even earlier work on Office 2003 -- was the bug in Excel's file format disclosed by the July security bulletin MS07-036. The vulnerability, which existed across the Office line, from version 2000 to 2007, was, said the bulletin, "in the way Excel handles malformed Excel files." It was the first bug in a core Office 2007 application's file format.

"Something slipped through the cracks," LeBlanc acknowledged after looking over the MS07-036 advisory. "We like to stop these things, and overall I think we did a pretty good job fuzzing Office 2007. This is the first one. It's kind of an example of why we need to continue to get smarter and apply more horsepower to this particular problem."

Bottom line, he said, is that the developers working on Office know they have to crank it up a notch. "We're going to be continuing to push the envelope to find new ways to make the product as secure as possible," LeBlanc said. "We need to get way, way out in front of those guys."

Join the Good Gear Guide newsletter!

Error: Please check your email address.
Rocket to Success - Your 10 Tips for Smarter ERP System Selection
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Gregg Keizer

Show Comments

Most Popular Reviews

Latest Articles


PCW Evaluation Team

Matthew Stivala

HP OfficeJet 250 Mobile Printer

The HP OfficeJet 250 Mobile Printer is a great device that fits perfectly into my fast paced and mobile lifestyle. My first impression of the printer itself was how incredibly compact and sleek the device was.

Armand Abogado

HP OfficeJet 250 Mobile Printer

Wireless printing from my iPhone was also a handy feature, the whole experience was quick and seamless with no setup requirements - accessed through the default iOS printing menu options.

Azadeh Williams

HP OfficeJet Pro 8730

A smarter way to print for busy small business owners, combining speedy printing with scanning and copying, making it easier to produce high quality documents and images at a touch of a button.

Andrew Grant

HP OfficeJet Pro 8730

I've had a multifunction printer in the office going on 10 years now. It was a neat bit of kit back in the day -- print, copy, scan, fax -- when printing over WiFi felt a bit like magic. It’s seen better days though and an upgrade’s well overdue. This HP OfficeJet Pro 8730 looks like it ticks all the same boxes: print, copy, scan, and fax. (Really? Does anyone fax anything any more? I guess it's good to know the facility’s there, just in case.) Printing over WiFi is more-or- less standard these days.

Ed Dawson

HP OfficeJet Pro 8730

As a freelance writer who is always on the go, I like my technology to be both efficient and effective so I can do my job well. The HP OfficeJet Pro 8730 Inkjet Printer ticks all the boxes in terms of form factor, performance and user interface.

Michael Hargreaves

Windows 10 for Business / Dell XPS 13

I’d happily recommend this touchscreen laptop and Windows 10 as a great way to get serious work done at a desk or on the road.

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?