A Vietnamese hacker managed to break into Perth International Airport's computer systems and steal a "significant amount" of sensitive security details and building plans. Le Duc Hoang Hai, 31, used the credentials of a third-party contractor to illegally access the airport's systems in March last year, The West Australian reported on Monday (11 December).

According to Prime Minister Malcolm Turnball's cybersecurity adviser Alastair MacGibbon, systems involving radars, aircraft operations and travelling passengers were not impacted in the breach.

Perth Airport detected the intrusion and notified the Australian Cyber Security Centre in Canberra and the Australian Federal Police of the breach. After the hack was traced back to Vietnam, the AFP informed their counterparts in the country whose subsequent investigation led to Hai's arrest.

He was convicted in a Vietnamese military court and sentenced to four years in jail.

Hai has targeted other critical infrastructure in the past as well and compromised numerous Vietnamese websites including those of telecom firms, banks and an online military newspaper. However, Perth Airport is believed to have been his only Australia-based target.

"Based on evidence gathered by the Australian Federal Police, it appears that credit card theft was the motivation for the illegal accessing of our system," Kevin Brown, CEO of Perth Airport, said in a statement to Nine.com.au. "No personal data of members of the public, such as details of credit card numbers, was accessed but other Perth Airport documents were taken."

MacGibbon said there is currently no evidence that he was working with a larger hacking group or that the information stolen in the breach was sold or leaked online. He also warned that the incident is a "sign of the type of work we are going to be doing a lot more of in the future".

He also warned that exploiting the details of a third-party contractor to target and compromise critical infrastructure is becoming an increasingly common security concern.

Over the past year, numerous companies have been targeted by hackers or had sensitive data exposed online due to errors committed by a third party firm.

"We completed a full and thorough risk assessment of the data that had been accessed to ensure there had been no threat to the safety of the travelling public," Brown said. "At no time was the safety or security of the airport, its staff, passengers or partners compromised."