ZDI-11-267: RealNetworks Realplayer MP3 ID3 tags Remote Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-267

August 16, 2011

-- CVE ID:
CVE-2011-2949

-- 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 11363. 
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 ID3v2 Tags.
RealPlayer creates a fixed size buffer for certain tags and will then
populate them with the data from the file. It uses a call to
WideCharToMultiByte to convert the data, but fails to take into account
that converting a single wide char might result in more then two
multi-byte chars. This causes more data to be written into the fixed
buffer then anticipated resulting in a heap buffer overflow.

-- 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:
    * Sean de Regge

-- About the Zero Day Initiative (ZDI):
Established by TippingPoint, The Zero Day Initiative (ZDI) represents 
a best-of-breed model for rewarding security researchers for responsibly
disclosing discovered vulnerabilities.

Researchers interested in getting paid for their security research
through the ZDI can find more information and sign-up at:

    http://www.zerodayinitiative.com

The ZDI is unique in how the acquired vulnerability information is
used. TippingPoint does not re-sell the vulnerability details or any
exploit code. Instead, upon notifying the affected product vendor,
TippingPoint provides its customers with zero day protection through
its intrusion prevention technology. Explicit details regarding the
specifics of the vulnerability are not exposed to any parties until
an official vendor patch is publicly available. Furthermore, with the
altruistic aim of helping to secure a broader user base, TippingPoint
provides this vulnerability information confidentially to security
vendors (including competitors) who have a vulnerability protection or
mitigation product.

Our vulnerability disclosure policy is available online at:
    http://www.zerodayinitiative.com/advisories/disclosure_policy/

Follow the ZDI on Twitter:
    http://twitter.com/thezdi