Microsoft has released two Critical updates:
MS11-057 (Internet Explorer): This security update resolves 5 privately reported vulnerabilities and 2 publicly disclosed vulnerabilities in Internet Explorer. The most severe of these vulnerabilities could allow remote code execution if a user views a specially crafted webpage using Internet Explorer. Microsoft is not aware of any attacks leveraging the vulnerabilities addressed in this bulletin.
MS11-058 (DNS Server): This security update resolves 2 privately reported vulnerabilities in Windows DNS server. The more severe of these vulnerabilities could allow remote code execution if an attacker sends a specially crafted Naming Authority Pointer (NAPTR) query to a DNS server. Servers that do not have the DNS role enabled are not at risk.
Users should install these updates as soon as possible.