Kernel software installed and running inside a Guest VM may exploit memory shared with the GPU Firmware to write data outside the Guest's virtualised GPU memory.
Exploitability
AV:LAC:LPR:NUI:NScope
S:UImpact
C:LI:LA:H7.3/CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:HOther