ZDI-08-044: Mozilla Firefox CSSValue Array Memory Corruption Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-08-044
July 17, 2008

-- CVE ID:
CVE-2008-2785

-- Affected Vendors:
Mozilla Firefox

-- Affected Products:
Mozilla Firefox 2.0.x
Mozilla Firefox 3.0.x

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-- 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.

The specific flaw exists in the browser's handling reference counters to
the nsCSSValue:Array class. Creating more then 65,535 references will
overflow a 16-bit reference counter and therefore result in an erroneous
free() while the object still exists. Properly manipulated this can
result in arbitrary code execution under the context of the current
user.

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

http://www.mozilla.org/security/announce/2008/mfsa2008-34.html

-- Disclosure Timeline:
2008-06-17 - Vulnerability reported to vendor
2008-07-17 - Coordinated public release of advisory

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

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