Three of the six bulletins are rated critical, Microsoft s highest severity rating. The most serious issues affect the company’s Internet Explorer browser, including the newest IE 8 on Windows 7. The vulnerabilities could allow remote code execution if a user views a specially crafted Web page using Internet Explorer. All five of the IE vulnerabilities were purchased by a third-party company that buys software flaw information in exchange for the exclusive rights to broker the disclosure process with affected vendors. Microsoft also shipped three important bulletins to cover the following.
Source: https://threatpost.com/microsoft-patches-critical-ie-windows-vulnerabilities-120809/73228/