Microsoft Office XP Data Validation Record Parsing Remote Code Execution Vulnerability

2011-04-12T00:00:00
ID ZDI-11-121
Type zdi
Reporter Aniway (Aniway.Anyway AT gmail DOT com)
Modified 2011-11-09T00:00:00

Description

This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Microsoft Office Excel. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.

The specific flaw exists within the application's parsing of a particular record within a Microsoft Excel Compound Document. When specifying a particular value, the application will fail to initialize a variable that is used as the length of a memcpy operation. Due to the usage of the uninitialized value, with proper control of the program flow an attacker can force a length of their own choosing for the memcpy operation. This will cause a buffer overflow and can lead to code execution under the context of the application.