Once again, Microsoft finds itself defending against a serious security issue. Windows Metafile is a native vector graphics file format. This allows for efficient rendering of graphics. But Windows also uses it to store sessions and house temporary data. The “zero-day exploit” came into the wild at the end of last year. Many variants had occurred by the first week of January. Many of these exploits utilize iframes in Internet Explorer on a malicious site. This iframe then redirects users to a metafile, which is downloaded, opens a backdoor and installs a keylogger. If the user is logged in as an administrator, then the hacker essentially has full control of the machine. Microsoft issued an “out of cycle” security patch because of the severity of the exploit. You may have seen a recent Windows update issuing against malicious software. The underlying cause, the vulnerability in the metafile architecture, won’t be able to be fixed for another six to eight months.
