ZDI-11-001: Microsoft Data Access Components DSN Overflow Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-001

January 11, 2011

-- CVE ID:
CVE-2011-0026

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

-- Affected Vendors:
Microsoft

-- Affected Products:
Microsoft Data Access Components

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TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 10763.
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-- Vulnerability Details:
This vulnerability allows attackers to execute arbitrary code on
vulnerable installations of Microsoft Data Access Components. The
vulnerability is present in an API call and as such successful
exploitation will depend on an application's implementation of this
call.

The specific flaw exists within the SQLConnectW call in the odbc32.dll
component. When calculating the size of a user provided szDSN, the
result of a call to lstrlenW is used in a signed comparison to
SQL_MAX_DSN_LENGTH to verify the destination buffer size. This value is
later used to copy user supplied data to a fixed length stack buffer. A
malicious szDSN length could be used to exploit this signedness bug and
execute arbitrary code.

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

http://www.microsoft.com/technet/security/bulletin/MS11-002.mspx

-- Disclosure Timeline:
2010-06-23 - Vulnerability reported to vendor
2011-01-11 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * AbdulAziz Hariri

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