Fortinet Discovers Microsoft Office Excel Memory Corruption Vulnerability

Summary

Fortinet's FortiGuard Labs has discovered a memory corruption vulnerability in Microsoft Office Excel.
Microsoft Office is an office suite of applications, servers and services. It was first announced by Microsoft in 1988. The first version of Office contained Microsoft Word, Microsoft Excel and Microsoft PowerPoint. Over the years, Office applications have grown substantially closer with shared features such as a common spell checker, OLE data integration and Visual Basic for Applications scripting language. Microsoft also positions Office as a development platform for line-of-business software under the Office Business Applications brand.
A memory corruption vulnerability was discovered in Microsoft Excel that could allow malicious users to create remote code execution conditions. The defect in question involves a read access violation when Excel incorrectly parses a value that makes Excel fall into the incorrect execution path. Attackers can leverage this behavior to control the flow of execution.

Solutions

FortiGuard Labs released the following FortiGate IPS signature which covers this specific vulnerability:

MS.Excel.Execution.Path.Parsing.Code.Execution
Released Oct 16, 2015
Users should apply the solution provided by Microsoft.

Acknowledgement

This vulnerability was discovered by Kai Lu of Fortinet's FortiGuard Labs.

IPS Subscription

Fortinet customers who subscribe to Fortinet's intrusion prevention (IPS) service should be protected against this vulnerability with the appropriate configuration parameters in place. Fortinet's IPS service is one component of FortiGuard Subscription Services, which also offer comprehensive solutions such as antivirus, Web content filtering and antispam capabilities. These services enable protection against threats on both application and network layers. FortiGuard Services are continuously updated by FortiGuard Labs, which enables Fortinet to deliver a combination of multi-layered security intelligence and true zero-day protection from new and emerging threats. These updates are delivered to all FortiGate, FortiMail and FortiClient products. Fortinet strictly follows responsible disclosure guidelines to ensure optimum protection during a threat's lifecycle.