by Michael Smith (Veshengro)
Here we go again...
Microsoft has warned customers to apply a temporary security fix to protect against a serious, newly discovered security bug in all supported versions of Windows.
The vulnerability results from the way Windows processes web pages containing MIME-formatted content. Attackers can exploit the weakness to run malicious scripts that steal sensitive information, spoof trusted websites or carry out other actions not authorized by the user. Internet Explorer is the only attack vector for the vulnerability, which resides in the Windows implementation of the MHTML protocol.
Microsoft's security team is still studying the flaw and “will take the appropriate action” once the investigation is complete. In the meantime, the company is advising Windows users to install a temporary “fix it” found at http://support.microsoft.com/kb/2501696 to prevent attacks. The measure disables some legitimate script execution and ActiveX functionality within MHT documents, but these side effects are, so it is claimed, mostly limited.
The Microsoft security team is also working with website operators, including Google, to explore possible server-side fixes as well. Potential fixes include filtering newline characters out of requests and responses, prepending newline characters onto HTTP responses, and altering the status code of HTTP responses.
However, as this problem is only a problem when MS Internet Explorer (IE) is being used the measure that is easiest, I should think, for most Windows users is to make use an alternate browser, since IE is the only known attack vector.
Enough alternative browsers are available, many which are based on the Mozilla Firefox one, and thus, also because of its many add-on that will make browsing safer still, I would suggest the use of Firefox above all others, though Opera is another good choice.
Another proof, if any more would be needed, as to the serious vulnerability of Internet Explorer, regardless of versions.
© 2011
