No

A cyber attack is a cyber operation, whether offensive or defensive, that is reasonably expected to cause injury or death to persons or damage or destruction to objects.

Michael Schmitt et al; Tallinn Manual 1.0, pp 92
  • Cyber Operation?
  • Expected to cause death or injury to people or objects?
Chinese Military Linked Cyber Espionage Operation on Japanese Defense Industrial Base does not match this definition. Here's a list of actual cyberattacks and and why this matters.

What happened?

A chinese systems engineer, who is also a member of the Chinese Communist Party, was charged for allegedly taking part in a cyber operation that targeted the Japan Aerospace Exploration Agency (JAXA) and 200 other Japanese companies and research institutions in 2016 and 2017.