Why it matters: It's the first time that NATO, a military alliance founded in 1949 to confront the Soviet Union, has signed onto a formal condemnation of China's cyber activities.
Zoom in: Authorities are detailing more than 50 different techniques that Chinese state-sponsored actors used, and offering up recommended mitigations that businesses and organizations can take.
The U.S. says that China's Ministry of State Security is using contract hackers to conduct the attacks, many of which are being done for profit, including via ransomware.
The U.S., NATO, European Union, U.K., Australia, Canada, New Zealand and Japan say they can now, "with high confidence," attribute the March attack using the Exchange flaw to cyberattackers affiliated with China's state security ministry. That attack crippled thousands of computers around the world.