ZDI-10-271: RealNetworks RealPlayer RTSP GIF Parsing Remote Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-10-271

December 10, 2010

-- CVE ID:
CVE-2010-4376

-- 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 8308.
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 media file.

The specific flaw exists in the parsing of GIF87a files over the
streaming protocol RTSP. When specifying a large Screen Width size in
the Screen Descriptor header a calculation on the destination heap
chunks size is improperly checked for overflow. This leads to a smaller
buffer being allocated and subsequently a heap overflow when processing
the received data. Exploitation of this vulnerability can lead to system
compromise under the credentials of the currently logged in user.

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

http://service.real.com/realplayer/security/12102010_player/en/

-- Disclosure Timeline:
2009-06-25 - Vulnerability reported to vendor
2010-12-10 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * Anonymous

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