A security feature bypass vulnerability exists when Microsoft Internet Explorer improperly handles requests involving UNC resources. An attacker who successfully exploited the vulnerability could force the browser to load data that would otherwise be restricted. In a web-based attack scenario, an attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft Internet Explorer and then convince a user to view the website. The attacker could also take advantage of compromised websites, and websites that accept or host user-provided content or advertisements. These websites could contain specially crafted content that could exploit the vulnerability. The security update addresses the vulnerability by modifying how affected Microsoft Internet Explorer handles requests involving UNC resources.