This security update resolves one publicly disclosed and forty privately reported 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. An attacker who successfully exploited these vulnerabilities could gain the same user rights as the current user. Customers whose accounts are configured to have fewer user rights on the system could be less impacted than those who operate with administrative user rights.
Revision Note: V1.1 (March 4, 2015): Revised bulletin to clarify what additional updates will be installed, and how they will be installed, when security update 3021952 is installed on systems running Internet Explorer 9, Internet Explorer 10, or Internet Explorer 11. See the Update FAQ for more information. This is an informational change only. There were no changes to the update files. Customers who have already successfully updated their systems do not need to take any action.