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ZDI-11-338 : RealNetworks RealPlayer IVR MLTI Chunk Length Parsing
Remote Code Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-11-338
November 28, 2011

- -- CVE ID:
CVE-2011-4258

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

- -- Affected Vendors:

RealNetworks



- -- Affected Products:

RealNetworks RealPlayer



- -- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of RealNetworks Real Player. 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 how the application parses a header
defined within a .ivr file. When parsing this header the application
will explicitly trust a 16-bit value denoting an size and use it for
performing an allocation. The code then uses a different value in the
file to populate the buffer. Due to the difference in values used for
allocation and the copy, this can be used to overwrite data outside the
bounds of the buffer which can lead to code execution under the context
of the application.

- -- Vendor Response:

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

http://service.real.com/realplayer/security/11182011_player/en/



- -- Disclosure Timeline:
2011-08-12 - Vulnerability reported to vendor
2011-11-28 - Coordinated public release of advisory

- -- Credit:
This vulnerability was discovered by:

* Damian Put


* Luigi Auriemma



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