Defence contractor had IT systems hacked as government reveals cyber attacks jumped by 15 per cent

An Australian defence contractor is among the victims caught up in online scams and fraud incidents which Australia's cyber security watchdog says increased by 15 per cent in the past year.

File photo Source: AAP

The Australian Cyber Security Centre's 2017 Threat Report, released on Tuesday by the minister responsible Dan Tehan, identified 47,000 cyber incidents over the year - half of which were online scams or fraud.

Among the attacks was a serious breach of the computer system of a defence contractor in November 2016.

Mr Tehan said in that incident, revealed for the first time on Tuesday, a significant amount of data had been stolen and the ACSC watched as the attacker accessed the network.

"Analysis showed that the malicious actor gained access to the victim's network by exploiting an internet or public-facing server, which they accessed using administrative credentials," the minister said.

"Once in the door, the adversary was able to establish access to other private servers on the network.

"The ACSC worked with the affected company to remediate the compromise, remove the malicious actor and provide tailored advice on how to prevent this happening in the future."

The ACSC also reported 7,283 of the cyber security incidents affected major Australian businesses.

Mr Tehan said online attacks on private sector systems of national interest and critical infrastructure were also becoming more elaborate and sophisticated.

"Business for cybercriminals is booming across the nation and it is impacting all of us," Mr Tehan told the National Press Club in Canberra.

The solution lay in more government agencies, businesses and individuals reporting attacks and cooperating to improve cyber security.

One of the biggest global threats over the year was the WannaCry ransomware attack, which impacted more than 200,000 people and created economic losses in the hundreds of millions of dollars.

However small businesses were also being affected.

Mr Tehan says business email compromise in Australia had cost an estimated $20 million over the past year.

The typical example involved a criminal gaining access to a business' email system, intercepting emails such as invoices and forging them to redirect money to another bank account.