DDoS Attacks (Part I) - Staying Master of Your Domain. IMG: (J. Anderson)
A recent spate of attacks launched in April involved the use of distributed denial of service (DDoS) attacks on the DNS server of a well-known worldwide organization. This blitz worked in achieving every goal a “hacktivist” could dream of: garnering global attention through strategic targeting to raise awareness for its cause.
Needless to say, DDoS attacks are now top of mind for every company in terms of securing their online presence. But not every company knows what is at risk – and more importantly – what they can do to keep their organization safe and secure. This is why over the next few weeks, I’ll be discussing:
- Examples of what can be targeted during a DDoS attack
- What your organization can do in the short term
- How you can protect your online presence in the long term
First and foremost, let’s talk about the most commonly targeted piece of equipment today. Pity the poor DNS: It’s critically important for every online operation, and yet it gets so little respect.
DNS, or the Domain Name System, is a hierarchical distributed naming system for just about any resource on the Internet, from servers to services, directly connected to the Internet, or even a private network. Since there are domain names associated with each entity in a network, a DNS request translates queries into IP addresses to identify other devices and services across the Internet. Simply put, DNS is the phone book of the Internet era.
Unfortunately, there’s one group of people that definitely respects the value of DNS: hackers. This is particularly true of the sub-group generally referred to as hacktivists. For the most part, these are not for-profit criminals out to steal information they can then misuse, or sell to others who will; they’re like-minded, loosely affiliated individuals who work together to target corporations and government agencies because they want to bring attention to a particular cause or just draw attention to their prowess.
Whatever the motive, these individuals understand that the effects of targeting DNS can be devastating, and they have made attacks on DNS their weapon of choice. They know that by taking out a DNS server, they’ve taken out the organization.
Perhaps the most popular tool among hacktivists to be aware of is the LOIC, or the Low Orbit Ion Cannon, an open-source network stress testing and DOS application that’s now available on numerous open-source platforms. The LOIC tool has been used very publicly against DNS servers, but it’s important to remember that attacks using this tool can be quite specifically aimed at other “sleeper targets” as well: e-mail, Web applications, IPv6 and firewalls.
For example, hacktivists understand that e-mail servers are a company’s communications lifeline. Disabling the e-mail server in any form can cripple every aspect of daily operations. A connection/syn floods on common mail ports, such as POP3, IMAP and SMTP is one of the simplest ways hacktivists can shut down all e-mail correspondence. But also be aware that some DDoS attacks go directly for the webmail URL, which prevents employees from using webmail apps. Using the LOIC is particularly effective in this category.
Another favored target is the Web application — a target-rich area, since most organizations typically have so many. From login forms to search pages, many of these interface directly with a key internal database. A targeted hacktivist attack looking to exploit the Web app can disable a database, which in some cases effectively disables the corporate site, and ultimately hampers critical business functions.
Many sites also use third-party pages, or widgets. Sophisticated hacktivists conduct detailed page analyses to identify outgoing communications, then focus on taking those components out. Site visitors then find each page slow or even unable to load.
Firewalls are even more problematic. These are an essential component of virtually every information security program — they allow specific network transmissions while denying unauthorized access. Yet an attack that looks to create an all-purpose block prevents external corporate offices from getting online, and the firewall becomes a significant liability. In these attacks, the key is to drive the use of the firewall’s CPU up to 100 percent, or full capacity. In other words, the very devices and services used to defend against external threats now serve to compound those attacks.
For the record though, it’s not all doom and gloom. There have been enough of these DDoS attacks in the industry to get a sense of how organizations should respond — along with what they do right and what mitigation techniques work in protecting against a DDoS attack. Stay tuned for more information, and I’ll look to give you the best practices I have seen so far to immediately address a DDoS attack in the short term, and what you really need to do to fully address the problem.
Miguel Ramos is the Senior Product Manager of Neustar, Inc., a provider of real-time information and analysis to the Internet, telecommunications, entertainment, advertising and marketing industries throughout the world.