The nation’s spy boss has sounded the alarm on the threat of sophisticated Chinese government hackers launching attacks on Australian critical infrastructure assets such as airports, telecommunications networks and the energy grid.

ASIO director-general Mike Burgess said that authoritarian regimes such as Russia and China are increasingly willing to target critical infrastructure assets to cause economic damage, undermine rivals’ military capabilities and sow social discord.

He raised the prospect of recent telecommunications outages – such as the Optus Triple Zero fiasco in October that caused three deaths – being repeated with malevolent intent by foreign actors seeking to cause chaos in Australian society.

“I have previously said we’re getting closer to the threshold for high-impact sabotage,” Burgess told an Australian Securities and Investments Commission forum in Melbourne on Wednesday.

“Well, I regret to inform you, we’re there now.”

In a clear reference to China, Burgess said: “ASIO is aware of one nation state – no prizes for guessing which one – conducting multiple attempts to scan and penetrate critical infrastructure in Australia and other Five Eyes countries, targeting water, transport, telecommunications, and energy networks.

“The reconnaissance is highly sophisticated, using top-notch tradecraft to find your networks, test for vulnerabilities, knock on digital doors and check the digital locks.

“And when they have penetrated your networks, they actively and aggressively map your systems, and seek to maintain persistent undetected access that enables them to conduct sabotage at a time and moment of their choosing.”

Burgess said that Chinese hacking groups Salt Typhoon and Volt Typhoon had probed telecommunications networks in Australia, as well as the United States.

Salt Typhoon, believed to be operated by China’s Ministry of State Security, launched major telecommunications cyberattacks against US companies in 2023 and 2024, while Volt Typhoon targeted US military facilities in Guam and other sensitive assets.

“I do not think we – and I mean all of us – truly appreciate how disruptive, how devastating, this could be.”

ASIO boss Mike Burgess

Referring to the Volt Typhoon hacking group, which is believed to operate on behalf of the Chinese government, Burgess said: “The hackers compromised American critical infrastructure networks to pre-position for potential sabotage.

“The penetrations gave China the ability to turn off telecommunications and other critical infrastructure.

“And yes, we have seen Chinese hackers probing our critical infrastructure as well.”

He continued: “I do not think we – and I mean all of us – truly appreciate how disruptive, how devastating, this could be.”

Referring to recent isolated and accidental telecommunications outages, Burgess said: “Imagine the implications if a nation state took down all the networks, or turned off the power during a heatwave, or polluted our drinking water, or crippled our financial system.

“I assure you these are not hypotheticals – foreign governments have elite teams investigating these possibilities right now.”

Burgess said cyber espionage attacks were “more than foreseeable, they are inevitable, literally happening every day”.

“And as I said earlier, we have now reached the threshold for high-impact sabotage,” he said.

“Nation states have been building capability for decades, but their intent has been to commit espionage and foreign interference, to steal and meddle.

“With global tensions rising, some are more likely to pull the trigger on the higher-harm activities.”

His rhetoric marks an escalation from his annual threat assessment in February, when he said the nation was “getting closer to the threshold for high-impact sabotage”.

Burgess said a recent plot in which Russian intelligence operatives planned to put explosive devices in packages on cargo planes headed from Europe to North America showed the growing risk of sabotage to democratic societies.

While physical sabotage remains possible, he said that cyber-enabled sabotage presented a more pressing concern for Australia because it is low-cost and deniable while still capable of causing significant damage.

Burgess last week gave a major speech in which he warned that at least three foreign governments were willing to try to murder dissidents in Australia.

He urged business leaders and boards to take the threat of cyberattacks more seriously, saying: “Complexity is not an excuse; it must be dealt with.”

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