Microsoft Office Web Components is prone to a remote code-execution vulnerability. An attacker may exploit this issue by enticing victims into opening a maliciously crafted HTML document. Successfully exploiting this issue allows remote attackers to execute arbitrary code in the context of the application using the ActiveX control (typically Internet Explorer). Failed exploit attempts will likely result in denial-of-service conditions.
Run all software as a nonprivileged user with minimal access rights.
To reduce the impact of latent vulnerabilities, always run nonadministrative software as an unprivileged user with minimal access rights.
Do not follow links provided by unknown or untrusted sources.
Attackers could exploit this vulnerability by enticing a user to visit a malicious website. Do not follow links provided by sources of questionable integrity.
Set web browser security to disable the execution of script code or active content.
Since a successful exploit of this issue allows malicious code to execute in web clients, consider disabling support for script code and active content within the client browser. Note that this mitigation tactic might adversely affect legitimate websites that rely on the execution of browser-based script code.
Do not open email messages from unknown or untrusted individuals.
Attackers could exploit this vulnerability through HTML email messages. Never accept any email from sources of questionable integrity.
Microsoft has released an advisory and fixes to address this issue. Please see the references for more information.