ZDI-11-205: Adobe Shockwave Missing Lctx Chunk Remote Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-205

-- CVE ID:
CVE-2011-0335

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

-- Affected Vendors:
Adobe

-- Affected Products:
Adobe Shockwave Player

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 11319. 
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 Adobe Shockwave. 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 parsing of the RIFF-based Director
file format that Shockwave utilizes. When parsing such files, the code
within the dirapi.dll module expects to find a chunk with a fourCC value
of Lctx. The code does not consider the possibility that one may not
exist and in that scenario if fails to properly initialize certain
values that are used later on in parsing other chunks. By removing the
Lctx chunk and also filling heap memory, an attacker can take advantage
of the uninitialized values to write values to an arbitrary location in
memory. This can be leveraged to execute remote code under the context
of the user running the browser.

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

http://www.adobe.com/support/security/bulletins/apsb11-17.html

-- Disclosure Timeline:
2011-04-11 - Vulnerability reported to vendor
2011-06-14 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * Luigi Auriemma

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