ZDI-11-308 : Cisco WebEx Player ATAS32.DLL linesProcessed Remote Code Execution Vulnerability

ZDI-11-308 : Cisco WebEx Player ATAS32.DLL linesProcessed Remote Code
Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-11-308
October 26, 2011

– CVE ID:
CVE-2011-4004

– CVSS:
9, AV:N/AC:L/Au:N/C:P/I:P/A:C

– Affected Vendors:

Cisco

– Affected Products:

Cisco WebEx

– Vulnerability Details:
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.

– Vendor Response:

Cisco has issued an update to correct this vulnerability. More details
can be found at:

http://www.cisco.com/go/psirt

– Disclosure Timeline:
2011-05-12 - Vulnerability reported to vendor
2011-10-26 - Coordinated public release of advisory

– Credit:
This vulnerability was discovered by:

• Aniway ([email protected])

• Anonymous

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