An issue was discovered in QEMU through 5.1.0. An out-of-bounds memory access was found in the ATI VGA device implementation. This flaw occurs in the ati2dblt() routine in hw/display/ati2d.c while handling MMIO write operations through the atimm_write() callback. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service.