ZDI-11-196: Microsoft Internet Explorer HTTP 302 Redirect Remote Code Execution Vulnerability
June 14, 2011
-- CVE ID: CVE-2011-1262
-- CVSS: 7.5, (AV:N/AC:L/Au:N/C:P/I:P/A:P)
-- Affected Vendors: Microsoft
-- Affected Products: Microsoft Internet Explorer 9 Microsoft Internet Explorer 8
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-- Vulnerability Details: This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Microsoft Internet Explorer. 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 way Internet Explorer handles HTTP 302 redirects to CDL protocols. When Internet Explorer tries to determine who is responsible for handling the protocol redirect it fails to keep a correct reference counter to a Transaction object which results in a use-after-free vulnerability. This can be leveraged into remote code execution under the context of the current user.
-- Vendor Response: Microsoft has issued an update to correct this vulnerability. More details can be found at:
-- Disclosure Timeline: 2011-04-04 - Vulnerability reported to vendor 2011-06-14 - Coordinated public release of advisory
-- Credit: This vulnerability was discovered by: * Peter Winter-Smith
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