A number of sensitive Federal Government and corporate networks – including some holding highly confidential plans for a geostationary communications satellite – have been penetrated by sophisticated cyber attacks, according to an ABC Four Corners investigation.

Austrade and the Defence Department’s elite Defence Science Technology Group, have both suffered significant cyber infiltrations by hackers based in China, according to Four Corners.

Four Corners has claimed that Australian satellite company Newsat, which went into administration last year, was so comprehensively infiltrated that its entire network had to be rebuilt in secret.

The Prime Minister’s cyber security adviser, Alastair MacGibbon, told the program the Government is “attacked on a daily basis” but declined to elaborate. “We don’t talk about all the breaches that occur,” he said. ”

Former CIA chief Michael Hayden, a former US National Security Agency head, said Australia and the US should harden up their defences to protect their data.

A spokesman for the Chinese Embassy in Canberra denied China had conducted any cyber espionage against Australian interests, calling such allegations “totally groundless” and “false clichés”. “Like other countries, China suffers from serious cyber attacks and is one of the major victims of hacking attacks in the world,” he said.