We all know that the software developed by Microsoft has vulnerabilities, that is the reason for many of their updates. However, this article is talking about the company itself, not just their products, getting hacked. The bug reporting system that is maintained by Microsoft so they can find areas for vulnerabilities was hacked back in 2013, and Microsoft is just now admitting it. At the time of the hack, Microsoft employees only had to enter a password to access the system. Since the hack, Microsoft has implemented a Multifactor Authentication (MFA) method.
https://thehackernews.com/2017/10/microsoft-bug-tracking-breach.html
Writing for the Information Professions, Fall 2017 