Microsoft is releasing a security advisory to help ensure customers are aware that an update to the Microsoft Malware Protection Engine also addresses a security vulnerability reported to Microsoft. The update addresses a privately reported vulnerability that could allow elevation of privilege if the Microsoft Malware Protection Engine scans a system after an attacker with valid logon credentials has created a specially crafted registry key. An attacker who successfully exploited the vulnerability could gain the same user rights as the LocalSystem account. The vulnerability could not be exploited by anonymous users.
Since the Microsoft Malware Protection Engine is a part of several Microsoft anti-malware products, the update to the Microsoft Malware Protection Engine is installed along with the updated malware definitions for the affected products. Administrators of enterprise installations should follow their established internal processes to ensure that the definition and engine updates are approved in their update management software, and that clients consume the updates accordingly.
Typically, no action is required of enterprise administrators or end users to install this update, because the built-in mechanism for the automatic detection and deployment of this update will apply the update within the next 48 hours. The exact time frame depends on the software used, Internet connection, and infrastructure configuration.