​Attack on Australian Census site didn’t register on global DDoS sensors

Commercial distributed denial of service (DDoS) monitors seemingly failed to detect what the Australian Bureau of Statistics (ABS) says was a series of DDoS attacks that sabotaged the country's nationwide census and has spawned a day of recriminations and investigations at the highest levels of government.

The Census Web site – which was to manage the country's first-ever all-online census – was experiencing spotty availability throughout the day and eventually went offline around 7:30pm amidst an escalating flood of complaints on social media. Some 2 million Australian households – out of approximately 10 million total – successfully lodged their census details through the site before it was shut down for what the ABS said in a statement was “four Denial of Service attacks yesterday of varying nature and severity”.

While the ABS blamed the outage on external forces, observers were wondering whether the agency had simply failed to anticipate demand – particularly since it was still tweeting to encourage citizens to visit the site as late as 9:54 pm. Others noted that the Digital Attack Map – a continuous map of DDoS attacks around the world, drawn from real-time data collected by DDoS specialist Arbor Networks – showed no significant DDoS activity in Australia during the period when the Census was being run; indeed, attack traffic in August has been almost non-existent compared with spikes in June and July, and a relatively massive surge between February and April.

DDoS attacks were increasingly being employed by dissenters and were “one of the easiest and most visible ways to voice that dissent,” Dan Holden, director of Arbor Networks' Security Engineering and Response Team (ASERT) told CSO Australia in the wake of the ABS outages.

Although he could not make judgements about the specific protections around the Census, Holden noted that “any site generally related to government and public services is often not very well protected. And the Internet is a place where geopolitical conflict, or any sort of local conflict in the physical world, is replayed on the Internet. It's human nature.”

As to why the alleged strong DDoS attacks didn't show up in the attack-monitoring statistics – an omission that some online have said suggests the problem actually stemmed from the ABS's failure to adequately stress-test its Census infrastructure – Holden noted that the omission may suggest that it didn't take much for the DDoS perpetrators to take down the site.

“DDoS is very much a measurable attack,” he explained. “If it doesn't take that much to knock you down, that's what attackers are after. They gauge the attack and adjust it accordingly. They only do whatever it takes to get the job done.”

The attack has sent the ABS into defensive mode and the government – which has this year significantly ramped up its rhetoric against cybercriminals in the wake of a successful breach of the Bureau of Meteorology by allegedly Chinese hackers last year – scrambling to evaluate the damage amidst assurances that the public's private information was still secure.

Yet experts have warned that it's still too early to rule out a hack, with DDoS attacks often used to distract from other, more subtle attacks.

Even as Privacy Commissioner Timothy Pilgrim fast-tracked an investigation into the day's events, security observers were weighing in on the situation, which has implications for the government's digital-transformation agenda as well as for the integrity of the core data set that feeds much of the government's planning and policymaking.

Dr Jon Oliver, senior architect at security firm Trend Micro, warned that the attacks may have been cover for other, more insidious activity and said in a statement that he has “complete confidence that the ABS was prepared for cyber attacks. Part of the problem is that they are collecting online a dataset of very high value in a short period of time, and anything of that value (with some controversy as well) will attract all manner of attackers including potentially sophisticated attackers.”

Professor Greg Austin, of the Canberra-based Australian Centre for Cyber Security (ACCS), said the attack left “room to question just how much the government is prepared to spend on this new challenge... Maybe we need some institutional innovation in the structures of government and a different conversation with the public about the threats.”

Noting that the ABS has reported 14 separate data breaches since 2013, Webroot senior information security analyst Dan Slattery said that DDoS attacks are “hard to stop. Every server that is connected to the Internet is in some ways vulnerable... The best way to mitigate the effectiveness of a DDoS attack is to plan ahead.”

Tags IT managementABScensusAustralian Bureau of StatisticsAustralian GovernmentDDoS attackshackedhacking scandal

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