Flaw Forces Microsoft E-Com Site to Go Offline

One of Microsoft Corp.s key e-commerce sites is currently offline after a security researcher found that the site was vulnerable to a common security problem known as cross-site scripting.

The Microsoft Developer Store at Developerstore.com has been unavailable for several days, and there is no indication when it may be back online.

An Argentine security researcher named Cesar Cerrudo on Friday posted a message to a security mailing list warning of the vulnerability on Microsofts site and said that he had informed the Redmond, Wash., software company of the problem. He later posted an e-mail exchange he had on Wednesday with a Microsoft Security Response Center representative, who said that he would pass the information on to the development team.

When the flaw wasnt fixed, Cerrudo sent his advisory to SecurityFocus.coms Vuln-Dev mailing list. The moderator of the list, Blue Boar, held the message until Friday while he contacted Microsoft personally and informed them of the impending public disclosure of the vulnerability.

Microsoft responded by taking the Developer Store site offline. As of 11 a.m. EST Monday it was still unavailable.

Cross-site scripting is a common vulnerability that enables an attacker to inject random code into certain fields on a Web site and can result in the attacker gaining access to supposedly private customer data.

When Cerrudos advisory finally hit the Vuln-Dev list on Friday, Blue Boar included a message of his own explaining his reasons for delaying its release.

“Youre welcome to cry censorship, limited disclosure, hypocrisy, etc … [but] this is in line with my policy for the list,” Blue Boar wrote. “In most cases I will not allow a post that contains info on how to nail a unique site.

“I post the information now, because I think that despite the fact that the problem is now gone, it is important to have a track record so that you can be informed about the security of a site you might do business with,” he wrote.

For his part, Cerrudo said he decided to post the information in the hopes of forcing Microsoft to act and only did so after contacting the company and finding that the problem had not been resolved.

“It was a critical hole. It took me 10 seconds to find it,” Cerrudo wrote. “I contacted Microsoft and more than 12 hours later they havent fix (sic) it. I think that Microsoft or the company [responsible] never say, We are sorry it was our mistake, we only want your money and quickly, we havent time to do that, where do you want to go tomorrow? “

In a terse, unsigned statement issued Monday afternoon, Microsoft said the company “is committed to keeping customers information safe and is working with the third-party vendor that operates the developerstore.com website to ensure that information is not compromised. This is an outsourced site. Microsoft does not manage the site nor is it part of our corporate network. However, we are working with the third party vendor to determine the accuracy of the report and to address any vulnerabilities if they exist.”