ZDI-11-225: Mozilla Firefox nsXULCommandDispatcher Remote Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-225

June 21, 2011

-- CVE ID:
CVE-2011-0085

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

-- Affected Vendors:
Mozilla

-- Affected Products:
Mozilla Firefox

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 11404. 
For further product information on the TippingPoint IPS, visit:

    http://www.tippingpoint.com

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

The specific flaw exists within the nsXULCommandDispatcher.cpp source
code. During a NS_XUL_COMMAND_UPDATE event dispatch, the user is able to
force command dispatcher to remove all the updaters in the mUpdaters
chain including the one that is currently in use. As a result, the local
variable updater becomes a stale pointer and updater->mNext refers to
memory previously freed. Successful exploitation can lead to code
execution in the context of the browser.

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

http://www.mozilla.org/security/announce/2011/mfsa2011-23.html

-- Disclosure Timeline:
2011-04-04 - Vulnerability reported to vendor
2011-06-21 - Coordinated public release of advisory

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

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