ZDI-11-310 : Adobe Reader Compound Glyph Index Sign Extension Remote
Code Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-11-310
October 26, 2011

-- CVE ID:
CVE-2011-2441

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

-- Affected Vendors:

Adobe



-- Affected Products:

Adobe Reader



-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Adobe Reader. 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 Adobe Reader handles compound
glyphs. When a glyph has more then 0x7FFF 'numberOfContours' a sign
extension occurs resulting in a buffer under-read. Simple glyphs are
checked when Adobe Reader parses the font info, but the value for
'numberOfContours' in an compound glyph is the sum of all its child
glyphs, and this is not checked. This could result in remote code
execution under the context of the current user.

-- Vendor Response:

Adobe has issued an update to correct this vulnerability. More details
can be found at:

http://www.adobe.com/support/security/bulletins/apsb11-24.html



-- Disclosure Timeline:
2011-07-20 - Vulnerability reported to vendor
2011-10-26 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:

* binaryproof



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