Zero-Day Advisory

Fortinet Discovers Mozilla Products Graphic Rendering Memory Corruption Vulnerability


Fortinet's FortiGuard Labs has discovered a memory corruption vulnerability in various Mozilla products, allowing a remote attacker to compromise targeted systems upon viewing malicious HTML document.


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

Released Sep 24, 2008
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Additional Information

The vulnerability lies in common graphics routines rendering, and is caused by insufficient checking of long strings when displaying them. There are two main attack scenarios:
1) A malicious html page could be hosted on a rogue or hacked web server, targeting users who browse the page in Firefox or Seamonkey.
2) A malicious html formatted e-mail could be mailed (or mass-mailed), targeting recipients who open the e-mail in Thunderbird or Seamonkey.


David Maciejak of Fortinet's FortiGuard Global 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.