Vulnerability Note VU#205948

Microsoft PowerPoint contains a vulnerability that could be exploited when PowerPoint opens a specially crafted document. The vulnerability is caused by incorrect handling of malformed records, which can cause memory corruption. This vulnerability affects both Windows and Mac versions of PowerPoint.

By convincing a user to open a specially crafted PowerPoint document, an attacker could execute arbitrary code with the privileges of the user running PowerPoint. If the user is logged in with administrative privileges, the attacker could take complete control of a vulnerable system. This vulnerability may also cause PowerPoint to crash.

Apply an update

This vulnerability is addressed in Microsoft Security Bulletin MS07-015. Microsoft Security Bulletin MS06-058 attempted to address the problem but the fix was not sufficient.

Do not open untrusted PowerPoint documents

Do not open unfamiliar or unexpected PowerPoint or other Office documents, particularly those hosted on web sites or delivered as email attachments. Please see Cyber Security Tip ST04-010.

Disable automatic opening of PowerPoint documents

By default, PowerPoint 97 and PowerPoint 2000 will configure Internet Explorer to automatically open PowerPoint documents. This feature can be disabled by using the Office Document Open Confirmation Tool. Mozilla Firefox users should disable automatic opening of files, as specified in the Securing Your Web Browser document.

Do not rely on file name extension filtering

In most cases, Windows will call PowerPoint to open a document even if the document has an unknown file extension. For example, if presentation.qwer contains the correct file header information, Windows will open presentation.qwer with PowerPoint. Filtering for common extensions (e.g., .ppt, .pot, and .pps) will not detect all PowerPoint documents. Additionally, a PowerPoint file with no file extension will also open with the PowerPoint application.