Canada's biggest airline says an unauthorized group briefly breached an internal system linked to the personal information and records of some employees.
Air Canada says in a statement today that no customer information was accessed in the cyberattack.
The Montreal-based company says flight operation systems and public-facing platforms were unaffected.
It says it has contacted people whose information was involved and has notified relevant authorities.
With all systems now back in full swing, Air Canada says it has implemented further security upgrades to prevent future incidents.
The company is the latest to fall victim to the endless string of cyberattacks that have plagued Canadian companies, which so far this year range from Suncor Energy to grocery giant Empire.