DEF CON 32 - Bug Hunting In VMware Device Virtualization - JiaQing Huang, Hao Zheng, Yue Liu

VMware's visualization security contains critical vulnerabilities in USB and SCSI device emulation, enabling privilege escalation and arbitrary code execution via out-of-bounds reads, memory management flaws, and uninitialized memory access. 2:08 6:00 14:02 16:00 28:07 33:06

Key Takeaways:
• USB emulation suffers from uninitialized memory and dangling pointers, leading to type confusion and buffer overflows during device transfers 17:00 22:00.
• A critical out-of-bounds read exists in VMX’s USB device handling due to incorrect port number modification during transfer release, causing memory corruption 23:00.
• The smart card reader fails to validate APD message length against urb buffer size, enabling out-of-bounds writes to host memory 25:00.
• SCSI data flow diverges between ESXi and Workstation, with ESXi’s VMkernel lacking heap size validation in unmap commands, allowing arbitrary memory access 31:00 37:00.
• VM-level security is inherently fragile, with device emulation and hypervisor code vulnerable to exploitation via USB or SCSI commands 26:29.

These findings reveal deep architectural weaknesses in VMware’s virtualization stack, exposing exploitable attack surfaces across device emulation layers.

Sources:

• [2:08](https://www.youtube.com/