Former Mozilla security chief Window Snyder has been hired by Apple.

Snyder started her new job Monday, where she's now working as a senior security product manager, according to sources familiar with the situation.

Apple is the third browser-maker in the past five years that has employed Snyder, who previously had worked as a security strategist at Microsoft where she managed the company's relationships with security consultants and had worked on the Windows XP and Windows Server 2003 operating systems.

Snyder took a job with Mozilla in 2006 and was credited with professionalizing the Firefox security response team, at a time when the open-source browser was increasingly coming under attack from hackers. She left Mozilla in late 2008, and worked as a consultant over the past year.

Well known in the security research community, Snyder joins a company that is generally viewed as aloof, if not hostile toward hackers.

Apple representatives could not be reached immediately for comment Monday night.