The Waltham, MA company has been issuing annual reports on Windows applications with the highest critical security problems. The most recent press release identifies "the Dirty Dozen," among which Firefox versions 2.x and 3.x rank at the top of the list, followed by Adobe Acrobat 8.1.2 and 8.1.1, Microsoft Windows Live (MSN) Messenger 4.7 and 5.1, Apple iTunes 3.2 and 3.1.2, and Skype 3.5.0.248.

According to Bit9, these applications have a few things in common. They run on Windows, are popular among users, and IT organizations don't consider them potentially malicious. The critical factors that put them on the Dirty Dozen list are that (a) at least one security hole was found, (b) they usually rely on users rather than IT admins to apply upgrades or patches, and (c) they can't be centrally updated with free enterprise tools. For the latter, Bit9 gives Microsoft's Systems Management Server (SMS) and Windows Server Update Services (WSUS) as examples.

Jonathan Nightingale from Mozilla's Human Shield group vehemently counters Bit9's assessment in a blog. He asserts that the "critical vulnerability reported in 2008" label penalizes software companies, such as Mozilla, with an open reporting policy about security problems. "To suggest that this openness is a weakness because it means that we have 'reported vulnerabilities' is to miss the reality: that software has bugs," he writes. For Nightingale, a more meaningful assessment would be to base "a product’s responsiveness to those bugs and its ability to contain them quickly and effectively."

Nightingale asserts that the vulnerabilities Bit9 found have long since been fixed, with most fixes within days of the announcement. He also considers Bit9's criticism of the lack of WSUS updating as ignoring real world experience in that Firefox's built-in update service spares users the trouble. "We consistently see 90% adoption within six days of a new update being released," he writes.