A heap buffer overflow flaw was found in QEMU's Cirrus CLGD 54xx VGA emulator's VNC display driver support before 2.9; the issue could occur when a VNC client attempted to update its display after a VGA operation is performed by a guest. A privileged user/process inside a guest could use this flaw to crash the QEMU process or, potentially, execute arbitrary code on the host with privileges of the QEMU process.
Exploitability
AV:AAC:HPR:LUI:NScope
S:CImpact
C:LI:LA:L5.5/CVSS:3.0/AV:A/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:LOther