A remote code execution vulnerability exists when Windows Shell improperly handles objects in memory. An attacker who successfully exploited this vulnerability could execute arbitrary code and take control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
In a web-based attack scenario, an attacker could host a website used to attempt to exploit the vulnerability. In addition, compromised websites and websites that accept or host user-provided content could contain specially crafted content that could exploit this vulnerability. An attacker would have no way to force users to visit a specially crafted website. Instead, an attacker would have to convince users to visit the website, typically by getting them to click a link in an email or instant message that takes them to the attacker's site.
The security update fixes this vulnerability by correcting how Windows Shell handles objects in memory.