SAN FRANCISCO (KGO) -- The vulnerability of the internet was exposed on Friday as a malicious attack made some of the country's best known websites inaccessible. Several Bay Area companies were victims. A heat map shows the outage on the internet. On it, you can see it encompasses both California and the Pacific Northwest.
IT engineer Jeffrey Fall quickly confirmed why users were having difficulty getting to Twitter by sending a ping.
"Twitter.com or www.twitter.com have no meaning now to the internet because it can't resolve to an IP address," he said. "And so, Twitter's off."
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Before daybreak, a malicious attack called a DDOS, or distributed denial of service, was overloading servers in the east that translate web addresses into the numbers that route you to a site.
The targets included well-known companies, such as Amazon, eBay, and Facebook. Complaints of a total blackout on Facebook made up half of the problems reported to a trouble site. Two other Bay Area sites, Google and Reddit, also had similar issues.
The attacker is unknown, although Stanford cyber security researcher Dr. Herbert Lin told us in a Skype interview that many have the capability.
"Anonymous is able to do this," he said. "There are various organized criminal elements operating out of various countries can do this. Some nation states could be doing this."
A DDOS is done by sending malicious code to any computer or smartphone user, which then uses that device as one of many to attack a server en masse. It could even be your home security system or other electronics connected to the internet.
"Security cameras, consumer electronics devices that are in homes," Intel Security Chief Technology Officer Steve Grobman said. "Really anything that's smart and connected that has vulnerability or a weakness could be compromised and then become part of the attack."
The White House says Homeland Security is trying to pinpoint the origin.