Researcher details of Amazon.com, MSN holes

Frustrated with what he calls a lack of response from Microsoft and Amazon.com, a security researcher has gone public with details of flaws on the two companies' Web sites.

The flaws could be used by attackers to steal "cookie" data files that would allow them to access Amazon.com and MSN accounts, or to display a fake login page that could be used in phishing attacks, according to Yash Kadakia, the independent security researcher who discovered the flaws.

Although the cross-site scripting flaws he discovered are generally considered to be low-risk problems, Kadakia's attack involves a technique called CRLF (Carriage Return Line Feed) injection, which can be used in a more serious and widespread attack, he said.

Kadakia said he first notified Microsoft of the problem about a year ago. But he said he was not taken seriously until late last week, when he posted screen shots of the flaw being exploited on his Web site.

The Amazon.com flaw was discovered in December, but after some initial discussions with the Web retailer, the vulnerability remained unpatched, Kadakia said. "The conversations got dropped off somewhere," he said.

A spokesman for Microsoft's public relations agency said the flaws were now being investigated. Amazon.com executives were unable to comment for this story.

Though Microsoft has made much of its focus on security, the company appears to be slower at dealing with security issues relating to its Web properties than with its software products, said Stefano Zanero, the co-founder and chief technology officer at security consultancy Secure Network SRL.

Web flaws such as the type discovered by Kadakia have been around for a long time, but hackers have tended to focus their efforts on operating systems. However, with operating system flaws now becoming harder to find, the bug hunters are looking for new areas, including Web applications.

According to Zanero, there are a lot more Web vulnerabilities to be discovered. "We do Web application penetration testing as one of our core business services, and we've found huge holes in every single Web application we've tested to date," he said. "This thing is just waiting to explode."

Earlier this month, a worm began making the rounds at Yahoo's Web-based e-mail server. Called JS.Yamanner@m, the worm did not cause widespread damage, but it drew attention to the vulnerability of some Web applications.

The slow response by Microsoft and Amazon.com shows that Web-based vulnerabilities are not a top concern to many Web sites, Zanero said. "It's the sluggish handling of these things that's surprising," he said. "These vulnerabilities were on two of the world's best-developed Web sites, somebody found them out, and nobody cared for a year or so."

Meanwhile, Amazon.com and Microsoft are now trying to fix the bugs, Kadakia said.

Not all security experts agreed that the bugs Kadakia has discovered are critical. "These are actually fairly common types of exploits," a Symantec spokesman said in an e-mail note. "Nothing really to write home about."

Nevertheless, Symantec appears to be taking the problem more seriously than does Microsoft, Kadakia said.

The security researcher recently notified Symantec about a similar flaw on its own Web site. "They fixed it in a week," he said.