ZDI-10-079: Realnetworks Helix Server NTLM Authentication Invalid Base64 Remote Code Execution Vulnerability Apr 28 2010 05:12PM
ZDI Disclosures (zdi-disclosures tippingpoint com)
ZDI-10-079: Realnetworks Helix Server NTLM Authentication Invalid Base64 Remote Code Execution Vulnerability
April 28, 2010

-- CVE ID:

-- Affected Vendors:

-- Affected Products:
RealNetworks Helix Server

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 6378.
For further product information on the TippingPoint IPS, visit:


-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of RealNetworks Helix Server. Authentication is
not required to exploit this vulnerability.

The specific flaw exists within the authentication provided by the
administrative web interface and is only present if it is configured to
use NTLM. The vulnerability can be triggered by specifying invalid
Base64 string within the Authorization header. If the string is not
proper Base64 the vulnerable function returns -1 which is not verified
and is later used as a length to a string copy routine.

-- Vendor Response:
RealNetworks states:
This issue has been addressed in v14:


-- Disclosure Timeline:
2009-07-14 - Vulnerability reported to vendor
2010-04-28 - Coordinated public release of advisory

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

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