Former employees reveal Microsoft suffered a data breach four and a half years ago. The tech giant’s bug-reporting and patch-tracking database for Windows contained information on critical and unpatched vulnerabilities in some of the most widely used software in the world. The hack was believed to be carried out by a highly-skilled corporate espionage hacking group known by various names, including Morpho, Butterfly and Wild Neutron, who exploited a JAVA zero-day vulnerability to hack into Apple Mac computers of Microsoft employees.
Source: https://thehackernews.com/2017/10/microsoft-bug-tracking-breach.html