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 ati_2d_blt() routine in hw/display/ati_2d.c while handling MMIO write operations through the ati_mm_write() callback. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service.

QEMU (aka Quick Emulator), when built with the VGA display emulator support, allows local guest OS privileged users to cause a denial of service (out-of-bounds read and QEMU process crash) via vectors involving display update.

The dhcp_decode function in slirp/bootp.c in QEMU (aka Quick Emulator) allows local guest OS users to cause a denial of service (out-of-bounds read and QEMU process crash) via a crafted DHCP options string.

The address_space_write_continue function in exec.c in QEMU (aka Quick Emulator) allows local guest OS privileged users to cause a denial of service (out-of-bounds access and guest instance crash) by leveraging use of qemu_map_ram_ptr to access guest ram block area.

An out-of-bounds read flaw was found in the QXL display device emulation in QEMU. The qxl_phys2virt() function does not check the size of the structure pointed to by the guest physical address, potentially reading past the end of the bar space into adjacent pages. A malicious guest user could use this flaw to crash the QEMU process on the host causing a denial of service condition.

The virgl_cmd_get_capset function in hw/display/virtio-gpu-3d.c in QEMU (aka Quick Emulator) built with Virtio GPU Device emulator support allows local guest OS users to cause a denial of service (out-of-bounds read and process crash) via a VIRTIO_GPU_CMD_GET_CAPSET command with a maximum capabilities size with a value of 0.

The virtio_gpu_set_scanout function in QEMU (aka Quick Emulator) built with Virtio GPU Device emulator support allows local guest OS users to cause a denial of service (out-of-bounds read and process crash) via a scanout id in a VIRTIO_GPU_CMD_SET_SCANOUT command larger than num_scanouts.

hw/pci/pci.c in QEMU 4.2.0 allows guest OS users to trigger an out-of-bounds access by providing an address near the end of the PCI configuration space.

sd_wp_addr in hw/sd/sd.c in QEMU 4.2.0 uses an unvalidated address, which leads to an out-of-bounds read during sdhci_write() operations. A guest OS user can crash the QEMU process.

In QEMU 5.0.0 and earlier, megasas_lookup_frame in hw/scsi/megasas.c has an out-of-bounds read via a crafted reply_queue_head field from a guest OS user.

An out-of-bounds heap buffer access issue was found in the ARM Generic Interrupt Controller emulator of QEMU up to and including qemu 4.2.0on aarch64 platform. The issue occurs because while writing an interrupt ID to the controller memory area, it is not masked to be 4 bits wide. It may lead to the said issue while updating controller state fields and their subsequent processing. A privileged guest user may use this flaw to crash the QEMU process on the host resulting in DoS scenario.

hw/rdma/rdma_backend.c in QEMU allows guest OS users to trigger out-of-bounds access via a PvrdmaSqWqe ring element with a large num_sge value.

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.

In QEMU 3.1, scsi_handle_inquiry_reply in hw/scsi/scsi-generic.c allows out-of-bounds write and read operations.

Quick Emulator (aka QEMU), when built with the Cirrus CLGD 54xx VGA Emulator support, allows local guest OS privileged users to cause a denial of service (out-of-bounds access and QEMU process crash) by leveraging incorrect region calculation when updating VGA display.

The vga_draw_text function in Qemu allows local OS guest privileged users to cause a denial of service (out-of-bounds read and QEMU process crash) by leveraging improper memory address validation.

The pnv_lpc_do_eccb function in hw/ppc/pnv_lpc.c in Qemu before 3.1 allows out-of-bounds write or read access to PowerNV memory.

In Qemu 3.0.0, lsi_do_msgin in hw/scsi/lsi53c895a.c allows out-of-bounds access by triggering an invalid msg_len value.

hw/display/cirrus_vga_rop.h in QEMU (aka Quick Emulator) allows local guest OS privileged users to cause a denial of service (out-of-bounds read and QEMU process crash) via vectors related to copying VGA data via the cirrus_bitblt_rop_fwd_transp_ and cirrus_bitblt_rop_fwd_ functions.

The sdhci_sdma_transfer_multi_blocks function in hw/sd/sdhci.c in QEMU (aka Quick Emulator) allows local guest OS privileged users to cause a denial of service (out-of-bounds heap access and crash) or execute arbitrary code on the QEMU host via vectors involving the data transfer length.

The cirrus_invalidate_region function in hw/display/cirrus_vga.c in Qemu allows local OS guest privileged users to cause a denial of service (out-of-bounds array access and QEMU process crash) via vectors related to negative pitch.

A DMA reentrancy issue leading to a use-after-free error was found in the e1000e NIC emulation code in QEMU. This issue could allow a privileged guest user to crash the QEMU process on the host, resulting in a denial of service.

In QEMU through 5.0.0, an assertion failure can occur in the network packet processing. This issue affects the e1000e and vmxnet3 network devices. A malicious guest user/process could use this flaw to abort the QEMU process on the host, resulting in a denial of service condition in net_tx_pkt_add_raw_fragment in hw/net/net_tx_pkt.c.

In QEMU 4.2.0, a MemoryRegionOps object may lack read/write callback methods, leading to a NULL pointer dereference.

QEMU 4.2.0 has a use-after-free in hw/net/e1000e_core.c because a guest OS user can trigger an e1000e packet with the data's address set to the e1000e's MMIO address.

QEMU (aka Quick Emulator), when built with the IDE disk and CD/DVD-ROM Emulator support, allows local guest OS privileged users to cause a denial of service (NULL pointer dereference and QEMU process crash) by flushing an empty CDROM device drive.

Stack-based buffer overflow in hw/usb/redirect.c in QEMU (aka Quick Emulator) allows local guest OS users to cause a denial of service (QEMU process crash) via vectors related to logging debug messages.

An integer overflow and buffer overflow issues were found in the ACPI Error Record Serialization Table (ERST) device of QEMU in the read_erst_record() and write_erst_record() functions. Both issues may allow the guest to overrun the host buffer allocated for the ERST memory device. A malicious guest could use these flaws to crash the QEMU process on the host.

Memory leak in the v9fs_device_unrealize_common function in hw/9pfs/9p.c in QEMU (aka Quick Emulator) allows local privileged guest OS users to cause a denial of service (host memory consumption and possibly QEMU process crash) via vectors involving the order of resource cleanup.

Memory leak in hw/9pfs/9p-handle.c in QEMU (aka Quick Emulator) allows local privileged guest OS users to cause a denial of service (host memory consumption and possibly QEMU process crash) by leveraging a missing cleanup operation in the handle backend.

QEMU (aka Quick Emulator) built with the Virtio GPU Device emulator support is vulnerable to a memory leakage issue. It could occur while updating the cursor data in update_cursor_data_virgl. A guest user/process could use this flaw to leak host memory bytes, resulting in DoS for a host.

QEMU (aka Quick Emulator) built with the ColdFire Fast Ethernet Controller emulator support is vulnerable to an infinite loop issue. It could occur while receiving packets in 'mcf_fec_receive'. A privileged user/process inside guest could use this issue to crash the QEMU process on the host leading to DoS.

The cirrus_do_copy function in hw/display/cirrus_vga.c in QEMU (aka Quick Emulator), when cirrus graphics mode is VGA, allows local guest OS privileged users to cause a denial of service (divide-by-zero error and QEMU process crash) via vectors involving blit pitch values.

Memory leak in hw/net/eepro100.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (memory consumption and QEMU process crash) by repeatedly unplugging an i8255x (PRO100) NIC device.

The v9fs_iov_vunmarshal function in fsdev/9p-iov-marshal.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (NULL pointer dereference and QEMU process crash) by sending an empty string parameter to a 9P operation.

The rc4030_write function in hw/dma/rc4030.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (divide-by-zero error and QEMU process crash) via a large interval timer reload value.

Memory leak in the ehci_process_itd function in hw/usb/hcd-ehci.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (memory consumption) via a large number of crafted buffer page select (PG) indexes.

The rocker_io_writel function in hw/net/rocker/rocker.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (out-of-bounds read and QEMU process crash) by leveraging failure to limit DMA buffer size.

Memory leak in the v9fs_xattrcreate function in hw/9pfs/9p.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (memory consumption and QEMU process crash) via a large number of Txattrcreate messages with the same fid number.

Memory leak in the v9fs_read function in hw/9pfs/9p.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (memory consumption) via vectors related to an I/O read operation.

Memory leak in the virtio_gpu_resource_create_2d function in hw/display/virtio-gpu.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (memory consumption) via a large number of VIRTIO_GPU_CMD_RESOURCE_CREATE_2D commands.

The serial_update_parameters function in hw/char/serial.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (divide-by-zero error and QEMU process crash) via vectors involving a value of divider greater than baud base.

The imx_fec_do_tx function in hw/net/imx_fec.c in QEMU (aka Quick Emulator) does not properly limit the buffer descriptor count when transmitting packets, which allows local guest OS administrators to cause a denial of service (infinite loop and QEMU process crash) via vectors involving a buffer descriptor with a length of 0 and crafted values in bd.flags.

Memory leak in the v9fs_write function in hw/9pfs/9p.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (memory consumption) by leveraging failure to free an IO vector.

Memory leak in the v9fs_link function in hw/9pfs/9p.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (memory consumption) via vectors involving a reference to the source fid object.

The mcf_fec_do_tx function in hw/net/mcf_fec.c in QEMU (aka Quick Emulator) does not properly limit the buffer descriptor count when transmitting packets, which allows local guest OS administrators to cause a denial of service (infinite loop and QEMU process crash) via vectors involving a buffer descriptor with a length of 0 and crafted values in bd.flags.

The net_tx_pkt_do_sw_fragmentation function in hw/net/net_tx_pkt.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (infinite loop and QEMU process crash) via a zero length for the current fragment length.

Use-after-free vulnerability in the vmxnet3_io_bar0_write function in hw/net/vmxnet3.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (QEMU instance crash) by leveraging failure to check if the device is active.

The virtqueue_map_desc function in hw/virtio/virtio.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (NULL pointer dereference and QEMU process crash) via a large I/O descriptor buffer length value.

The vmsvga_fifo_run function in hw/display/vmware_vga.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (out-of-bounds write and QEMU process crash) via vectors related to cursor.mask[] and cursor.image[] array sizes when processing a DEFINE_CURSOR svga command.