In recent filings with the Securities and Exchange Commission (SEC), Microsoft for the first time acknowledges that Mozilla's browsers pose a competitive threat and the software giant also notes that security vulnerabilities leave it open to legal action.

"Competitors such as Mozilla offer software that competes with the Internet Explorer Web browsing capabilities of our Windows operating system products," said Microsoft in the annual 10K Form it's required to file with the SEC. This is the first time that the Redmond, Wash.-based developer has referred to Mozilla by name in an SEC filing.

Although Microsoft last year named Linux as a competitive threat on the client side, Mozilla's browsers, particularly Firefox, only climbed out of obscurity to grab 8-10 percent of the browser share after Microsoft filed 2004's 10K.

CRN