Nov. 21, 2011 at 4:27 PM ET
AT&T has emailed customers that it "recently detected an organized and systematic attempt to obtain information on a number of AT&T customer accounts" online. But a company spokesman said no accounts have been breached, and estimates that less than 1 percent of customers are affected by the break-in attempt.
The hackers "appear to have used 'auto script' technology to determine whether AT&T telephone numbers were linked to online AT&T accounts," said AT&T spokesman Mark A. Siegel in a statement to msnbc.com.
"No accounts were breached and our investigation is ongoing to determine the source or intent of the attempt to gather this information," he said. "In the meantime, out of an abundance of caution, we are advising the account holders involved."
After news of Sony's PlayStation Network hack was reported last spring, Sony advised its customers to change their passwords. Not so in this case, AT&T says; "it's entirely up to them," said Siegel. If you use AT&T's online services, for example to check your bill online at "My AT&T," you may have received the email from the company.
In it, AT&T says that:
We have not yet determined the source or intent of the attempt to gather information, but we are continuing to investigate.
We do not believe that the perpetrators of this attack obtained access to your online account or any of the information contained in that account. Use of your mobile device or other AT&T services has not been affected by this incident.
... Because there may be an increased risk of fraudulent attempts to access your account information, you should be cautious about efforts to obtain sensitive information through email ("phishing") or text messages ("smishing").
This isn't the first time AT&T has faced the problem of intruders. Last year, hackers got into the company's iPad subscriber data, obtaining a list of 120,000 email addresses that also included celebrities, chief executives and politicians. Two men were arrested in connection with that crime.
If you want to learn more about safety from AT&T, check the company's website at att.com/safety.