Software Engineering Institute

Microsoft Publisher is a desktop publishing application that is provided with some versions of Microsoft Office. Microsoft Publisher fails to properly handle malformed publisher (.pub) documents, which can result in an exploitable situation. The vulnerabilities include: Out-of-bounds array indexing, invalid pointer use, and memory corruption.

By convincing a user to open a specially crafted Publisher document, a remote, unauthenticated attacker could execute arbitrary code with the privileges of the user running Publisher.

Apply an update

These issues are addressed in Microsoft Security Bulletin MS11-091. Please also consider the following workarounds:

Use the Microsoft Enhanced Mitigation Experience Toolkit

The Microsoft Enhanced Mitigation Experience Toolkit (EMET) can be used to help prevent exploitation of this and other vulnerabilities.

Enable DEP in Microsoft Windows

Consider enabling Data Execution Prevention (DEP) in supported versions of Windows. DEP should not be treated as a complete workaround, but it can mitigate the execution of attacker-supplied code in some cases. Microsoft has published detailed technical information about DEP in Security Research & Defense blog posts "Understanding DEP as a mitigation technology" part 1 and part 2. DEP should be used in conjunction with the application of patches or other mitigations described in this document.

Note that when relying on DEP for exploit mitigation, it is important to use a system that supports Address Space Layout Randomization (ASLR) as well. ASLR is not supported by Windows XP or Windows Server 2003 or earlier. ASLR was introduced with Microsoft Windows Vista and Windows Server 2008. Please see the Microsoft SRD blog entry: On the effectiveness of DEP and ASLR for more details.