Qemu: denial of service via improper synchronization in qemu nbd server during socket closure
A flaw was found in the QEMU NBD Server. This vulnerability allows a denial of service (DoS) attack via improper synchronization during socket closure when a client keeps a socket open as the server is taken offline.
Qemu-kvm: virtio-net: queue index out-of-bounds access in software rss
A flaw was found in the virtio-net device in QEMU. When enabling the RSS feature on the virtio-net network card, the indirections_table data within RSS becomes controllable. Setting excessively large values may cause an index out-of-bounds issue, potentially resulting in heap overflow access. This flaw allows a privileged user in the guest to crash the QEMU process on the host.
Qemu-kvm: 'qemu-img info' leads to host file read/write
A flaw was found in the QEMU disk image utility (qemu-img) 'info' command. A specially crafted image file containing a `json:{}` value describing block devices in QMP could cause the qemu-img process on the host to consume large amounts of memory or CPU time, leading to denial of service or read/write to an existing external file.
Qemu-kvm: virtio-pci: improper release of configure vector leads to guest triggerable crash
A flaw was found in the QEMU Virtio PCI Bindings (hw/virtio/virtio-pci.c). An improper release and use of the irqfd for vector 0 during the boot process leads to a guest triggerable crash via vhost_net_stop(). This flaw allows a malicious guest to crash the QEMU process on the host.
Qemu-kvm: net: assertion failure in update_sctp_checksum()
A flaw was found in QEMU. An assertion failure was present in the update_sctp_checksum() function in hw/net/net_tx_pkt.c when trying to calculate the checksum of a short-sized fragmented packet. This flaw allows a malicious guest to crash QEMU and cause a denial of service condition.
Qemu: virtio: dma reentrancy issue leads to double free vulnerability
A double free vulnerability was found in QEMU virtio devices (virtio-gpu, virtio-serial-bus, virtio-crypto), where the mem_reentrancy_guard flag insufficiently protects against DMA reentrancy issues. This issue could allow a malicious privileged guest user to crash the QEMU process on the host, resulting in a denial of service or allow arbitrary code execution within the context of the QEMU process on the host.
QEMU before 8.2.0 has an integer underflow, and resultant buffer overflow, via a TI command when an expected non-DMA transfer length is less than the length of the available FIFO data. This occurs in esp_do_nodma in hw/scsi/esp.c because of an underflow of async_len.
An issue was discovered in QEMU 7.1.0 through 8.2.1. register_vfs in hw/pci/pcie_sriov.c does not set NumVFs to PCI_SRIOV_TOTAL_VF, and thus interaction with hw/nvme/ctrl.c is mishandled.
An issue was discovered in QEMU 7.1.0 through 8.2.1. register_vfs in hw/pci/pcie_sriov.c mishandles the situation where a guest writes NumVFs greater than TotalVFs, leading to a buffer overflow in VF implementations.
Qemu: vnc: null pointer dereference in qemu_clipboard_request()
A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. The qemu_clipboard_request() function can be reached before vnc_server_cut_text_caps() was called and had the chance to initialize the clipboard peer, leading to a NULL pointer dereference. This could allow a malicious authenticated VNC client to crash QEMU and trigger a denial of service.
Qemu: virtio-net: stack buffer overflow in virtio_net_flush_tx()
A stack based buffer overflow was found in the virtio-net device of QEMU. This issue occurs when flushing TX in the virtio_net_flush_tx function if guest features VIRTIO_NET_F_HASH_REPORT, VIRTIO_F_VERSION_1 and VIRTIO_NET_F_MRG_RXBUF are enabled. This could allow a malicious user to overwrite local variables allocated on the stack. Specifically, the `out_sg` variable could be used to read a part of process memory and send it to the wire, causing an information leak.
Qemu: 9pfs: improper access control on special files
A flaw was found in the 9p passthrough filesystem (9pfs) implementation in QEMU. The 9pfs server did not prohibit opening special files on the host side, potentially allowing a malicious client to escape from the exported 9p tree by creating and opening a device file in the shared folder.
Qemu: improper ide controller reset can lead to mbr overwrite
A bug in QEMU could cause a guest I/O operation otherwise addressed to an arbitrary disk offset to be targeted to offset 0 instead (potentially overwriting the VM's boot code). This could be used, for example, by L2 guests with a virtual disk (vdiskL2) stored on a virtual disk of an L1 (vdiskL1) hypervisor to read and/or write data to LBA 0 of vdiskL1, potentially gaining control of L1 at its next reboot.
Qemu: vnc: infinite loop in inflate_buffer() leads to denial of service
A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. A wrong exit condition may lead to an infinite loop when inflating an attacker controlled zlib buffer in the `inflate_buffer` function. This could allow a remote authenticated client who is able to send a clipboard to the VNC server to trigger a denial of service.
Triggerable assertion due to race condition in hot-unplug
A flaw was found in QEMU. The async nature of hot-unplug enables a race scenario where the net device backend is cleared before the virtio-net pci frontend has been unplugged. A malicious guest could use this time window to trigger an assertion and cause a denial of service.
QEMU through 8.0.0 could trigger a division by zero in scsi_disk_reset in hw/scsi/scsi-disk.c because scsi_disk_emulate_mode_select does not prevent s->qdev.blocksize from being 256. This stops QEMU and the guest immediately.
An issue was discovered in TCG Accelerator in QEMU 4.2.0, allows local attackers to execute arbitrary code, escalate privileges, and cause a denial of service (DoS). Note: This is disputed as a bug and not a valid security issue by multiple third parties.
The hardware emulation in the of_dpa_cmd_add_l2_flood of rocker device model in QEMU, as used in 7.0.0 and earlier, allows remote attackers to crash the host qemu and potentially execute code on the host via execute a malformed program in the guest OS. Note: This has been disputed by multiple third parties as not a valid vulnerability due to the rocker device not falling within the virtualization use case.
QEMU through 8.0.4 accesses a NULL pointer in nvme_directive_receive in hw/nvme/ctrl.c because there is no check for whether an endurance group is configured before checking whether Flexible Data Placement is enabled.
Out-of-bounds read information disclosure vulnerability
A heap out-of-bounds memory read flaw was found in the virtual nvme device in QEMU. The QEMU process does not validate an offset provided by the guest before computing a host heap pointer, which is used for copying data back to the guest. Arbitrary heap memory relative to an allocated buffer can be disclosed.