The vmsvga_fifo_read_raw function in hw/display/vmware_vga.c in QEMU allows local guest OS administrators to obtain sensitive host memory information or cause a denial of service (QEMU process crash) by changing FIFO registers and issuing a VGA command, which triggers an out-of-bounds read.
The net_checksum_calculate function in net/checksum.c in QEMU allows local guest OS users to cause a denial of service (out-of-bounds heap read and crash) via the payload length in a crafted packet.
A heap buffer overflow was found in the floppy disk emulator of QEMU up to 6.0.0 (including). It could occur in fdctrl_transfer_handler() in hw/block/fdc.c while processing DMA read data transfers from the floppy drive to the guest system. A privileged guest user could use this flaw to crash the QEMU process on the host resulting in DoS scenario, or potential information leakage from the host memory.