A remote code execution vulnerability exists in Microsoft Project software when the software fails to check the source markup of a file. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker could 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. Exploitation of the vulnerability requires that a user open a specially crafted file with an affected version of Microsoft Project. In an email attack scenario, an attacker could exploit the vulnerability by sending a specially crafted project, or resource file, to the user and convince the user to open the file. The security update addresses the vulnerability by correcting how Microsoft Project checks the source code of a file.