By Byron Kaye
SYDNEY (Reuters) - International Business Machines Corp apologized to Australia on Tuesday for what the government has described as a "malicious" cyber-attack that shut down a national census, but blamed two domestic internet providers for the security lapse.
IBM was the lead contractor for the five-yearly August 9 household survey by the Australian Bureau of Statistics (ABS) which went offline that day after four distributed denial of service (DDoS) attacks, caused by the website being flooded with clicks.
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The breach embarrassed a government that has sought to impress voters with its cybersecurity credentials.
At a Senate inquiry into the matter, IBM Australia and New Zealand Managing Director Kerry Purcell said he apologized "unreservedly" for the inconvenience and added that he is negotiating a settlement with the government for failing to fulfill the A$10 million ($7.6 million) contract.
Purcell also said IBM was helping a police investigation, and declined to say who he suspected was behind the attack.
But he went on say that attacks were launched through a router in Singapore, and blamed Australian ISP Vocus Communications Ltd, a subcontractor of Nextgen Networks Pty Ltd, for failing to shut it down.
"We had repeated assurances from the ISP that the appropriate protocol was in place," Purcell told the inquiry.
"The primary root cause was through a router that was outside Australia."
In a written submission to the inquiry, IBM said its preferred anti-DDoS measure, which it calls "Island Australia", involves "geoblocking" or getting the company's ISPs to shut down offshore traffic coming into the country.
In a written submission to the inquiry, Nextgen said IBM told it about "Island Australia" six days before the census website went live in July, and that IBM declared a test of the strategy four days before the census a success.
It said Nextgen followed IBM's instructions, but noted that IBM rejected Nextgen's offer of additional anti-DDoS detection measures.
Vocus said in a submission that it told Nextgen the week before the census that it "did not provide geoblocking" and that "Vocus was in fact requested to disable its DDoS protection product covering the e-Census IP space".
It did not specify who gave that instruction.
($1 = 1.3149 Australian dollars)
(Reporting by Byron Kaye; Editing by Simon Cameron-Moore)