THE SECURITY THREAT OF A DDOS ATTACK
More importantly, in many cases a DDoS attack is merely designed to distract from other criminal activity, such as data theft or network infiltration. The attacker keeps its target busy fighting off the DDoS attack, to then sneak in a piece of malware.
FIVE MOST FAMOUS DDOS ATTACKS
In recent years, DDoS attacks have only been increasing in both frequency and severity. Here, we’ll examine five of the largest and most famous DDoS attacks.
1. GITHUB: 1.35 TBPS
On Feb. 28, 2018, GitHub—a popular developer platform—was hit with a sudden onslaught of traffic that clocked in at 1.35 terabits per second. If that sounds like a lot, that’s because it is—that amount of traffic is not only massive, it’s record-breaking.
According to GitHub, the traffic was traced back to “over a thousand different autonomous systems (ASNs) across tens of thousands of unique endpoints.”
What’s worse is that GitHub was not entirely unprepared for a DDoS attack—they simply had no way of knowing that an attack of this scale would be launched.
As GitHub explained in the incident report linked above, “Over the past year we have deployed additional transit to our facilities. We’ve more than doubled our transit capacity during that time, which has allowed us to withstand certain volumetric attacks without impact to users…. Even still, attacks like this sometimes require the help of partners with larger transit networks to provide blocking and filtering.”
2. OCCUPY CENTRAL, HONG KONG: 500 GBPS
The PopVote DDoS attack was carried out in 2014 and targeted the Hong Kong-based grassroots movement known as Occupy Central. The movement was campaigning for a more democratic voting system.
In response to their activities, attacker(s) sent large amounts of traffic to three of Occupy Central’s web hosting services, as well as two independent sites, PopVote, an online mock election site, and Apple Daily, a news site, neither of which were owned by Occupy Central but openly supported its cause. Presumably, those responsible were reacting to Occupy Central’s pro-democracy message.
The attack barraged servers with packets disguised as legitimate traffic, and was executed with not one, not two, but five botnets. This resulted in peak traffic levels of 500 gigabits per second.
3. CLOUDFLARE: 400 GBPS
In 2014, security provider and content delivery network CloudFlare was slammed by approximately 400 gigabits per second of traffic. The attack was directed at a single CloudFlare customer and targeted servers in Europe and was launched with the help of a vulnerability in the Network Time Protocol (NTP), a networking protocol for computer clock synchronization. Even though the attack was directed at just one of CloudFlare’s customers, it was so powerful that it affected CloudFlare’s own network.
This attack illustrated a technique in which attackers use spoofed source addresses to send mass amounts of NTP servers’ responses to the victim. This is known as “reflection,” since the attacker is able to mirror and amplify traffic.
Shortly after the attack, the U.S. Computer Emergency Readiness Team explained NTP Amplification Attacks are, “especially difficult to block” because “responses are legitimate data coming from valid servers.”
4. SPAMHAUS: 300 GBPS
In 2013, a DDoS attack was launched against Spamhaus, a nonprofit threat intelligence provider. Although Spamhaus, as an anti-spam organization, was and is regularly threatened and attacked, this DDoS attack was large enough to knock their website offline, as well as part of their email services.
Like the 2014 attack on CloudFlare mentioned above, this attack utilized reflection to overload Spamhaus’ servers with 300 gigabits of traffic per second.
The attack was traced to a member of a Dutch company named Cyberbunker, who seemingly targeted Spamhaus after it blacklisted Cyberbunker.
5. U.S. BANKS: 60 GBPS
In 2012, not one, not two, but a whopping six U.S. banks were targeted by a string of DDoS attacks. The victims were no small-town banks either: They included Bank of America, JP Morgan Chase, U.S. Bancorp, Citigroup and PNC Bank.
The attack was carried out by hundreds of hijacked servers, which each created peak floods of more than 60 gigabits of traffic per second.
At the time, these attacks were unique in their persistence: Rather than trying to execute one attack and then backing down, the perpetrator(s) barraged their targets with a multitude of methods in order to find one that worked. So, even if a bank was equipped to deal with a few types of DDoS attacks, they were helpless against other types.