How they've hacked you

Cybercriminals have a big tool chest of attacks they can use to breach systems and steal information. Here are some common methods.

Denial of Service
Denial of Service

Denial of Service attacks aren't technically "hacks," since they can be done without breaking into any systems. Typically, DoS attacks overwhelm a website's servers by flooding them with requests. That makes websites unreachable or unresponsive.

To bring down bigger sites, attackers will sometimes use botnets, or large numbers of infected computers, to send requests all at once. There's not much that Web companies can do to prevent that kind of attack except to get more servers.

"DoS attacks are very difficult to defend against," said Paul Asadoorian, CEO of security consultancy PaulDotCom Enterprises. "But attackers are not stealing any information when they do a DoS."

By David Goldman - Last updated July 29 2011: 5:11 AM ET
Join the Conversation
The cyber Mafia has already hacked you

Large, organized crime syndicates have been launching sophisticated attacks for decades.