The tech giant has accused a Chinese cyber-espionage group of the recent attacks on its mail server software.
In a blog post, Microsoft stated that the hackers came from a state-backed group, a “highly skilled and sophisticated actor” and they took advantage of four previously undetected intrusions in different versions of the software.
According to Microsoft’s Threat Intelligence Centre, it said its security flaws allowed the hackers to remotely access email inboxes and was carried out by sophisticated “Hafnium” a group evaluated to be state-sponsored and operating out of China usually conducts its operations primarily from leased virtual private servers in the US.
Microsoft based its conclusion on “observed victimology, tactics and procedures.
Hafnium targets higher education institutions, infectious disease researchers, law firms, non-governmental groups and defence contractors.
However, Microsoft had been attacked for the eighth time in the space of 12 months.