Researchers: Beware the IE Cache on a Public Terminal

If you use Internet Explorer to access Google's Gmail on public terminals, you may be leaving a lot of sensitive information exposed in the browser's cache, according to a warning from Web application security specialist Cenzic./p>

Cenzic issued an alert for what it argues are vulnerabilities in Gmail and IE that could "severely impact e-mail systems and user privacy."

However, Microsoft has downplayed the risk, insisting this is "not a product vulnerability."

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Cenzic spokesman Mandeep Khera said his company's researchers figured out a way to use CSRF (cross-site request forgery) in combination with the improper use of caching directives to hijack Gmail credentials from the IE cache.

The issue is specific to Gmail on IE and Cenzic believes both Microsoft and Google should apply fixes to secure customers, especially those using computer kiosks in a library or Internet café.

After a "thorough investigation," Microsoft has dismissed the threat as overblown. "In the scenario in question an attacker would need authenticated access to the system in order to modify files located in the cache. With that level of access, an attacker could install malicious programs that would have more impact than the scenarios described," a Microsoft spokesman said in a statement sent to eWEEK.

To read about the Web's 12 scariest applications, click here.

Cenzic's Khera acknowledged that the hacker must have physical access to the system to launch an attack but insists it presents a real cross-site scripting risk to end users who use public terminals.

"I understand Microsoft's position but that doesn't mean it's not a vulnerability. It's still a serious issue that needs to be patched," Khera said in an interview.

In the absence of a patch, Khera recommends that users disable caching of pages at the browser level, which will prevent any page from being cached for later viewing. This workaround may adversely affect the browsing experience, he warned.

Technical details of the issue has been sent to the US-CERT (U.S. Computer Emergency Response Team).

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