400 attacks per day: Behind Australia's growing DDoS attack surface

There is no denying that the number of DDoS attacks has been increasing everywhere around the world, new variants of attacking tools and techniques have been made available to the attackers much faster than we have seen in the past. Based on the statistics we have collected for Australia, the number of DDoS attacks have been increased roughly 25% each year, and we believe that number could become around 30,000 attacks per month by end of 2020.

The largest DDoS attack targeting Australia in 2017 is around 228 Gbps in June, although these kinds of multi-gigabit attacks always catch our attention, they don't really happen very often. Almost 80% of the DDoS attacks seen in Australia are under 2 Gbps, but still could possibly overwhelm the bandwidth of the internet connection for a lot of enterprises.

Another interesting observation is that the number of DDoS attacks between 10 to 50 Gbps has been steadily increasing from last year. Given the fact that the attackers are getting more weapons in their arsenal – for example, IoT and mobile devices, this means the size and frequency of the DDoS attacks will keep growing.

When we look at the countries where most of the DDoS attacks were being sourced, we have observed that countries such as the US, China, Korea, UK and Germany are usually at the top of the list. As DDoS attacks are typically sourced from infected computer devices (notnets), countries with a high computer population may also have a high infected rate, particularly if pirated software is being used to a large extent in that country.

In recent years, with the arrival of IoT botnets, such as Mirai, some Asian countries with a high deployment rate of IoT devices have also been seen as major sources of DDoS attacks.

If we turn our focus from the source country to the destination country being attacked most often, we then find the countries which are on the top of the list of the attacking sources, are also high on the list for the receiving side.

A possible reason could be that the high computer population and adoption rate in the country also means a lot of business is being conducted over the network, such as the financial sector, consumer sector, government and so on, giving the attackers more targets to aim for.