ZDI-10-176: Mozilla Firefox normalizeDocument Remote Code Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-10-176
September 13, 2010

-- CVE ID:
CVE-2010-2766

-- CVSS:
10, (AV:N/AC:L/Au:N/C:C/I:C/A:C)

-- Affected Vendors:
Mozilla Firefox

-- Affected Products:
Mozilla Firefox 3.6.x

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TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 10463. 
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    http://www.tippingpoint.com

-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Mozilla Firefox. User interaction is
required to exploit this vulnerability in that the target must visit a
malicious page or open a malicious file.

The flaw exists within the normalizeDocument function defined within
nsDocument.cpp. When handling children nodes the code does not account
for a varying number of children during normalization. An attacker can
abuse this problem along with the fact that the code does not validate
the child index is within bounds to access an invalid object and execute
arbitrary code under the context of the browser.

-- Vendor Response:
Mozilla Firefox has issued an update to correct this vulnerability. More
details can be found at:

http://www.mozilla.org/security/announce/2010/mfsa2010-55.html

-- Disclosure Timeline:
2010-07-20 - Vulnerability reported to vendor
2010-09-13 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * regenrecht

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