Zero-Day Advisory

Improper Memory Access Vulnerability in Multiple Microsoft Office Products


Fortinet's FortiGuard Labs has discovered improper memory access vulnerability in Multiple Microsoft Office Products.


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

Released Aug 16, 2006
Users should apply the solution provided by Microsoft.

Additional Information

There is a bug in Microsoft Portable Network Graphics Import Filter, which is used in many Windows products, and is located in C:\Program Files\Common Files\Microsoft Shared\Grphflt\PNG32.FLT.

An attacker may construct a malformed .png file. When users open it using a software which uses PNG32.FLT, such as Microsoft Photo Editor, the software will cause memory access violation. If specially crafted, it may cause execution of arbitrary code. This bug is due to manipulation of IDAT Image Data in PNG file.


Dejun Meng of Fortinet Security Research Team

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.