ZDI-11-268: RealNetworks RealPlayer SWF DefineFont Remote Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-268

August 16, 2011

-- CVE ID:
CVE-2011-2948

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

-- 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 11351. 
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 RealNetworks RealPlayer. 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 RealPlayer handles DEFINEFONT
fields in Flash Files. When the process parses corrupt a ShapeRecord
with the DefineFont record it reads outside a stack buffer and uses a
random stack value as a heap pointer. Later this pointer will be used to
write data into. The resulting corruption can lead to remote code
execution under the context of the current user.

-- Vendor Response:
RealNetworks has issued an update to correct this vulnerability. More
details can be found at:
http://service.real.com/realplayer/security/08162011_player/en/

-- Disclosure Timeline:
2011-04-01 - Vulnerability reported to vendor
2011-08-16 - Coordinated public release of advisory

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

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