Last week we told you about a huge data breach that was affecting Hotmail, Yahoo!, and GMail accounts – hundreds of thousands of them at last count. Now experts say that the amount of spam messages coming from those sites has shot up dramatically and believe those hacked accounts are to blame. The spams are personalized and were sent to the contacts in each account’s address book. Links in the spam messages lead to fake shopping sites set up to steal personal information such as credit and debit card numbers, names, addresses, and email addresses – a textbook phishing operation.
Some experts believe that the breach is just too large to have been achieved through phishing alone and suspect malware, mainly keyloggers, may have been involved as well.
“The quantity of people hit makes me think that it was key logging — the success rate for phishing is only about one in 1,000,” Amichai Shulman, chief technology officer for security firm Imperva, told ZDNet. “Secondly, when I went through the list of e-mail account credentials, there were entries with the same username, but a slightly different password, which suggests that they’re typos. I don’t think people would keep falling for a phishing scam and entering their details, it looks more like people are making mistakes and the key-logging software is recording them,” he said.
So far researchers have been unable to pinpoint the exact cause of the breach or determine who is responsible. They recommend that everyone, regardless of what email service they use, change their passwords immediately and then do so every six months. Passwords should be a combination of numbers and letters and every account you have should have its own unique password.