Denial of Service Attack Downs Twitter, hits Facebook

(This posting was updated with content on Facebook and botnets at 11.30 AM PT on Thursday Aug. 6.)

Twitter, the rising star among social networking Web sites, was downed on Thursday morning (Pacific Time) due to an apparent distributed denial of service attack. At the same time, Facebook also came under attack.

“On this otherwise happy Thursday morning, Twitter is the target of a denial of service attack,” Biz Stone, Twitter’s co-founder, wrote in a posting on Twitter’s blog Thursday morning. Facebook told Wired.com that it “encountered network issues related to an apparent distributed denial-of-service attack.” Facebook didn’t go down, but said the attack “resulted in degraded service for some users.”

So what is a distributed denial of service attack and why would somebody attack Twitter or Facebook?

In a distributed denial-of-service, or DDoS, attack, the target is overloaded with requests for information. The requests come from a large number of sources, typically compromised computers in a botnet run by cybercrooks. As a result, legitimate users can no longer access the site. Web site operators can defend against DDoS attacks by monitoring the traffic to their sites and filtering out malicious traffic using a firewall or other network security tool.

Distributed denial of service attacks happen for a variety of reasons. In this case it could simply be for the notoriety of taking down a high profile Web site like Twitter.com or Facebook, but it may also be for more nefarious reasons such as political motivations or to extort money. Hacktivism and extortion schemes are common online, the equivalent of disruptive protests in the streets and ‘protection money’ in the brick and mortar world.

Your PC may be used to attack Facebook and Twitter

The average computer user can’t do anything if a Web site is down due to an attack. However, users can prevent their computer from becoming part of the attacking force.

The compromised computers used to assault Web sites in a DDoS attack are typically unproteced PCs of unknowing computer users that have been commandeered by cybercriminals and networked into a botnet. To prevent this from happening, computer users should practice good PC hygiene by making sure the operating system and applications are up to date on patches and running current security software, such as the products sold by McAfee.  

To learn if you’re part of a botnet or became the victim of another cybercrime, you can scan your computer at no cost to you and get help from experts at the McAfee Cybercrime Response Unit.

DDoS History

While still common, most DDoS attacks today aren’t as high profile as they were nearly 10 years ago. Back in 2000 e-commerce giants eBay, Amazon.com and Buy.com, along with Yahoo, news site CNN.com, online trading sites E*Trade and Datek, and technology information provider ZDNet reported similar attacks. The sites were down, sometimes for days, and the FBI held press conferences about the spate of attacks.

McAfee is investigating the Twitter and Facebook attacks, our researchers are plowing through data to find out more about the make up of this particular attack.

Tags: Consumer, Cybercrime