Use-after-free vulnerability in hw/pci/pcie.c in QEMU (aka Quick Emulator) allows local guest OS users to cause a denial of service (QEMU instance crash) via hotplug and hotunplug operations of Virtio block devices.

QEMU (aka Quick Emulator) built to use 'address_space_translate' to map an address to a MemoryRegionSection is vulnerable to an OOB r/w access issue. It could occur while doing pci_dma_read/write calls. Affects QEMU versions >= 1.6.0 and <= 2.3.1. A privileged user inside guest could use this flaw to crash the guest instance resulting in DoS.

The VGA module in QEMU improperly performs bounds checking on banked access to video memory, which allows local guest OS administrators to execute arbitrary code on the host by changing access modes after setting the bank register, aka the "Dark Portal" issue.

The (1) BMDMA and (2) AHCI HBA interfaces in the IDE functionality in QEMU 1.0 through 2.1.3 have multiple interpretations of a function's return value, which allows guest OS users to cause a host OS denial of service (memory consumption or infinite loop, and system crash) via a PRDT with zero complete sectors, related to the bmdma_prepare_buf and ahci_dma_prepare_buf functions.