ASD incident response manager Mitchell Clarke told a conference in Sydney on Wednesday the hackers targeted a small "mum and dad type business" - an aerospace engineering company with about 50 employees in July past year. The hacker, he said, was codenamed Alf, after a well-known character, Alf Stewart, from the Australian TV soap opera Home and Away.
But according to Australian defence industry minister Christopher Pyne, the data was "commercial" not "military".
"It could be someone who was working for another company".
"While the Australian company is a national-security linked contractor and the information disclosed was commercially sensitive, it was unclassified", they said in a statement on Wednesday evening. In 2011 for example, a major Japanese defence contractor was hacked. The unnamed organization notified the ASD that it was hacked in November of 2016, and that outside parties gained access to its network.
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The federal minister for cybersecurity Dan Tehan revealed the breach earlier this week through the release of the Australian Cyber Security Centre's 2017 Threat Report, but provided no detail specifically about the Alf incident.
The 50-person aerospace engineering firm subcontracts to the Defence Department and had one person managing its IT functions.
However, he added that the theft did not pose any sort of risk to national security. "Collectively, the industry needs to embrace a new approach to security", said German.
That attack stole classified information about a top-secret weapons system, and US Deputy Defence Secretary William Lynn at the time blamed a foreign intelligence agency for the attack.
"Security thinking needs to change; organisations need to move away from the concept of owned and unowned networks or infrastructure and consider only users, applications and secure access - and the security industry must facilitate that shift". "This means that, in the inevitability of a breach occurring, the data to which hackers can gain access is constrained".
At a security conference in Sydney, ASD's Mitchell Clark said that the software used by the government contractor was relatively weak.