Denial of Service (DoS) attacks have been around about as long as computers have been network connected. A website’s purpose is to accept connections from the Internet and return information. A bad actor can take advantage of this setup to overwhelm the web server with so many connection requests that valid connections are denied. If your business relies on eCommerce to sell products, a DoS attack directly affects your revenue. For this reason, a lot of people work to find methods to guard against such attacks. And bad actors work to find new ways of overcoming such protections.
One method deployed by the bad actors is the Distributed Denial of Service (DDoS) attack. Many computers work together to attack a single target. Defenders put in new defences and attackers combine ever-larger collections of devices in a cyber arms race of sorts. This arms race took a new turn in 2016 when the Mirai botnet was unleashed against DNS servers showing how potent a DDoS attack can be. Leveraging consumer devices like home routers and webcams, Mirai was able to maintain a sustained attack of 640Gbps. This overwhelmed DNS servers in the United States making large portions of the Internet unavailable. There followed several equally high profile attacks and people woke up to the new reality.
In 2017, researchers uncovered a new botnet which is expanding on the tricks used by Mirai. In addition to scanning for default passwords, Reaper uses exploits to compromise more devices and grow the attack potential. There are disagreements about the specific size of the Reaper botnet, but everyone agrees it is a significant threat.
These major botnets are capable of impacting large portions of the Internet and getting into the headlines doing it. But there is another DoS story that is arguably more impactful and less well known. Over 28,00 DoS attacks occur on the Internet every day!
A group of researchers unveiled their findings at the recent AMC Internet Measurement Conference in London. They gathered data from DDoS Protection Services (DPS) , amplification honeypots, and a DNS measurement platform. The data showed that one-third of all /24 networks recently estimated to be active on the Internet have suffered at least one DoS attack over the last two years.
“Our results reveal the massive scale of the DoS problem, including an eye-opening statistic that one-third of all /24 networks recently estimated to be active on the Internet have suffered at least one DoS attack over the last two years. We also discovered that often targets are simultaneously hit by different types of attacks” reads the research paper published by the experts.
While large-scale attacks like Mirai and Reaper may get the headlines, this amount of DDoS attacking will have real impacts for the victims.
The researchers noted that victims are likely to engage DPS providers following an attack.
“One of the things we show is if a website is attacked, this creates an urgency for people to start outsourcing to protection services,” said Mattjis Jonker, one of the researchers from the University of Twente.
This early research sheds light on the breadth and scale of the problem beyond the headline-grabbing attacks.
“During this recent two-year period under study, the internet was targeted by nearly 30,000 attacks per day,” said Alberto Dainotti, one of the researchers from CAIDA (Center for Applied Internet Data Analysis)
“These absolute numbers are staggering, a thousand times bigger than other reports have shown.”
The researchers have also validated some assumptions about potential targets. The United States hosts around 25% of web addresses and received around 25% of DDoS attacks. Following a similar pattern, Google, GoDaddy, and Wix services host the most websites and also see the most attacks.
Following this early success, researchers are next planning to include more data including DoS attacks on email servers with the ultimate goal being DDoS protection solutions.
The researchers plan to investigate the impact of DoS attacks on mail infrastructure in future projects, they already instrumented a measurement infrastructure to query for more DNS RRs on the names found in MX records.