Australia's spy chief, David Irvine, has warned businesses to be on the alert for cyber attacks and corporate espionage.
Irvine, who is the director-general of the Australian Security Intelligence Organisation (ASIO), said that many cyber attacks were going undetected by local security agencies.
"I would be very surprised if we, who are active in this area, are picking up the greater proportion of it — in fact, quite the reverse," he told a business conference in Canberra on Monday.
"There's very much more going on than it is within the resources of the agencies to pick up, particularly in the private sector."
Company information, like planned investments and potential weak points of a business, were the constant targets of hackers, he warned.
He urged Australian businesses to be more proactive in protecting their company's information.
"Senior management needs to consider very carefully their security culture, and assess the threat and potential damage if they don't take action," Irvine said.
"They need to sit down and think very, very hard about what it is they need to protect."
So far in 2012, more than 5000 cases of cyber attacks have been reported to the attorney-general's Computer Emergency Response Team (CERT), Irvine said.
"That's reports received," he told an Australian Industry Group forum.
"There are more."
He also warned that cyber vandalism could have "significant social and economic impacts" on Australia.
For example, an attack on Australia's telecommunication networks could halt electronic transactions made through banks.
Irvine warned that critical infrastructure, like the electricity grid, transport system and national financial networks, could be shut down by cyber attacks.
Hackers could also neutralise or destroy a nation's military capabilities.
"The war-fighting capacity of most sophisticated militaries around the world is now extraordinarily dependent on the cyber world," he said.
Meanwhile, the spy chief repeated the agency's view that the threat of terrorist attacks had become "predominantly home-grown" and been assessed by ASIO to be "persistent and chillingly real".
The security agency's aim was to detect such attacks as early as possible.
"The longer you allow terrorist planning to go on, the more likely it is to get out of hand and for something terrible to happen," Irvine said.
The news follows the ISACA 2012 Governance of Enterprise IT survey, which found that Oceanic organisations were more likely to have had a security breach than those in the rest of the world. Around 29 per cent of Australian or New Zealand businesses who responded to the survey reported having had a security breach in the last 12 months, compared to 22 per cent of the global survey respondents.
Suzanne Tindal contributed to this article.