CVE-2011-4004

Desbordamiento de búfer en la funcionalidad de procesamiento de ATAS32 en Cisco WebEx Recording Format (WRF) T26 player anterior a EP40 SP49 y SP28 anterior a T27 permite a atacantes remotos ejecutar código arbitrario a través de un archivo modificado WRF.

This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Cisco WebEx Player. 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 in ATAS32.DLL during the parsing of values defined within the WRF file format. The vulnerable code trusts the linesProcessed value from the file, and uses it in some logic to determine the destination pointer for a memcpy. By supplying an overly large linesProcessed value, the subtraction would cause an integer underflow and allows an attacker control of the destination buffer pointer. This can be further leveraged to execute arbitrary code under the context of the current user.