Internet Explorer cross-frame-navigate security issue and patch

Microsoft has released a patch that fixes a recently discovered issue with cross frame security in Internet Explorer. Mac versions of Explorer are at risk. Details of the problem are covered on another Web page: "The Cross Frame Navigate issue involves a vulnerability in Internet Explorer 3 and 4 that could allow a clever hacker to circumvent Internet Explorer's security safeguards. This vulnerability makes it possible for a malicious Web site operator to read the contents of files on your computer." (Thanks, MacNN.)