ZDI-10-010: RealNetworks RealPlayer Skin Parsing Remote Code Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-10-010 
January 21, 2010

-- CVE ID:
CVE-2009-4246

-- Affected Vendors:
RealNetworks

-- Affected Products:
RealNetworks RealPlayer

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 8493. 
For further product information on the TippingPoint IPS, visit:

http://www.tippingpoint.com 

-- Vulnerability Details:
This vulnerability allows remote attackers to execute code on vulnerable
installations of RealNetworks RealPlayer. User interaction is required
in that a user must visit a malicious website or open a malicious file
and accept a dialog to switch player skins.

The specific flaw exists during parsing of malformed RealPlayer .RJS
skin files. While loading a skin the application copies certain variable
length fields from the extracted file named web.xmb into a statically
sized buffer. By crafting these fields appropriately an attack can cause
the process to overflow the buffer. This can be leveraged to execute
arbitrary code with the privileges 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/01192010_player/en/ 

-- Disclosure Timeline:
2009-01-15 - Vulnerability reported to vendor
2010-01-21 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
* Peter Vreugdenhil (security@petervreugdenhil.nl) 

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