VB-Audio Matrix Drivers Local Privilege Escalation via Kernel Memory Exposure

Summary

VB-Audio Matrix and Matrix Coconut (versions ending in 1.0.2.2 and 2.0.2.2 and earlier, respectively), contain a local privilege escalation vulnerability in the VBMatrix VAIO virtual audio driver (vbmatrixvaio64*_win10.sys). The driver allocates a 128-byte non-paged pool buffer and, upon receiving IOCTL 0x222060, maps it into user space using an MDL and MmMapLockedPagesSpecifyCache. Because the allocation size is not page-aligned, the mapping exposes the entire 0x1000-byte kernel page containing the buffer plus adjacent non-paged pool allocations with read/write permissions. An unprivileged local attacker can open a device handle (using the required 0x800 attribute flag), invoke the IOCTL to obtain the mapping, and then read or modify live kernel objects and pointers present on that page. This enables bypass of KASLR, arbitrary kernel memory read/write within the exposed page, corruption of kernel objects, and escalation to SYSTEM.