VMWare VMnc Codec Open-DML Standard Index dwSize Heap Overflow VulnerabilityTPTI-09-02: April 6th, 2009
Vulnerability DetailsThis vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of multiple VMWare products. User interaction is required in that a user must visit a malicious web page or open a malicious video file.
Upon installation VMWare Workstation, Server, Player, and ACE register vmnc.dll as a video codec driver to handle compression and decompression of the fourCC type 'VMnc'. This format is used primarily by Workstation to capture remote framebuffer recordings of sessions within a virtual machine. The resulting video is stored within an AVI container file. While playing back such files the function responsible for handling ICM_DECOMPRESS driver messages implicitly trusts a size value while decompressing a frame. Specifically, the dwSize element within an Open-DML standard index RIFF chunk is used as an argument to a memcpy into a static heap buffer. This can be leveraged to execute arbitrary code on the host system under the context of the current user.
Vendor ResponseVMWare, Inc. has issued an update to correct this vulnerability. More details can be found at:
2009-02-16 - Vulnerability reported to vendor
2009-04-06 - Coordinated public release of advisory