Telecom giant Qwest Communications acknowledged Thursday that a glitch in its Web-based paperless billing system left some long-distance customer records exposed for over a week.
Qwest offers long-distance customers a price break if they forgo printed statements and pay their bills with a credit card though the company's Web site. Subscribers who avail themselves of the service are offered a choice of logging in with a phone number and calling card PIN, or a user-specified name and password.
Earlier this month the system stopped checking passwords, allowing anyone who enters a valid username to access that subscriber's billing record, including the type of phone service for which they're signed-up, their name and billing address, the name on any calling cards issued though the account, and a complete copy of their most recent phone bill.
"An unauthorized user could go in there, if they knew the username, and they could go on there and look at billing information," said company spokesperson Barbara Faulhaber.
Examining the source code of the billing accounts preferences page also yielded the customer's credit card number and expiration date, according to users who reported the problem.
Only long-distance customers who opted for the paperless billing option were affected by the leak -- a similar system used by Qwest's local phone subscribers was not exposed.
Qwest took the site offline for several hours Thursday to close the hole. But two of the users who discovered the issue say they reported it to Qwest last week, and fault the company for not taking action faster.
William Shanks, a California software engineer, first contacted SecurityFocus about the hole last Friday, and says he reported it to Qwest the previous Wednesday, May 15th. "I can confirm that they have had a ticket, and a customer service person walked through the issue since Wednesday morning," wrote Shanks in an e-mail interview. "When I followed up on last Friday, they claimed that the group responsible for the Web services were aware of it, and had been since at least Thursday... In my opinion, the site should have been taken down on Wednesday until fixed."
Jason Hetherington, a Texas-based law student, says he reported the bug on Monday of last week, after a friend who uses the paperless billing system complained that his password had become irrelevant. "He was a Qwest customer who said he was having problems changing his password," says Hetherington. "He was changing it, and it was still letting him in."
But Qwest's Faulhaber says the company didn't learn of the hole until Wednesday, May 22nd. "As soon as this came to our attention, we took our site down and fixed it," says Faulhaber.
The Web hole was apparently introduced when Qwest changed the terms-of-service for the site, and added a click-through page for customers to accept the new agreement during the login process.
Among other things, the terms-of-service disclaim the company of any responsibility for unauthorized access to user accounts.
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