Five months after CBC News reported an attempt by four IT staff at the Montreal-based International Civil Aviation Organization to cover up their mishandling of a major cyberattack, a UN whistleblower is going public with accusations of misconduct against ICAO's top brass.

In November 2016, the International Civil Aviation Organization was hit by the most serious cyberattack in its history. Internal documents obtained by CBC suggest key members of the team that should have prevented the attack tried to cover up how badly it was mishandled.