Microsoft has released a security bulletin today that uncovers a vulnerability present in all versions of Windows from XP to current version. The vulnerability could allow a malicious script to hijack your browser session and steal personal data.
The weakness lies in the MHTML (MIME Encapsulation of Aggregate HTML) protocol handler which is used by applications to render results like Microsofts Internet Explorer. An attacker could exploit this weakness by luring a user to click a link that would execute the script and remain active for the rest of the browser session.
Affected Software Windows XP Service Pack 3 Windows XP Professional x64 Edition Service Pack 2 Windows Server 2003 Service Pack 2 Windows Server 2003 x64 Edition Service Pack 2 Windows Server 2003 with SP2 for Itanium-based Systems Windows Vista Service Pack 1 and Windows Vista Service Pack 2 Windows Vista x64 Edition Service Pack 1 and Windows Vista x64 Edition Service Pack 2 Windows Server 2008 for 32-bit Systems and Windows Server 2008 for 32-bit Systems Service Pack 2** Windows Server 2008 for x64-based Systems and Windows Server 2008 for x64-based Systems Service Pack 2** Windows Server 2008 for Itanium-based Systems and Windows Server 2008 for Itanium-based Systems Service Pack 2 Windows 7 for 32-bit Systems Windows 7 for x64-based Systems Windows Server 2008 R2 for x64-based Systems** Windows Server 2008 R2 for Itanium-based Systems
According to Microsoft, nobody has actively exploited this vulnerability yet. Although I would steer clear of Internet Explorer for the time being until the bug is fixed. There is a handy iFixit button on Technet that may fix the bug, try it out and let us know how it worked out for ya. Yet another bug for Microsoft lets see how fast they patch this one.