ZDI-11-159: Mozilla Firefox OBJECT mObserverList Remote Code Execution Vulnerability
May 10, 2011
-- CVE ID: CVE-2011-0066
-- CVSS: 9, (AV:N/AC:L/Au:N/C:P/I:P/A:C)
-- Affected Vendors: Mozilla
-- Affected Products: Mozilla Firefox
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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 or open a malicious file.
The specific flaw exists within Firefox's handling of observer OBJECTs. If an observer OBJECT is removed from the mObserverList during an iteration of LOOP_OVER_OBSERVERS macro, one can heap spray over |mObserverList.mNext| and change the execution flow. This would allow the attacker to execute arbitrary code under the context of the user running the browser.
-- Vendor Response: Mozilla has issued an update to correct this vulnerability. More details can be found at:
-- Disclosure Timeline: 2011-02-17 - Vulnerability reported to vendor 2011-05-10 - Coordinated public release of advisory
-- Credit: This vulnerability was discovered by: * regenrecht
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