A flaw was found in QEMU. If the QIOChannelWebsock object is freed while it is waiting to complete a handshake, a GSource is leaked. This can lead to the callback firing later on and triggering a use-after-free in the use of the channel. This can be abused by a malicious client with network access to the VNC WebSocket port to cause a denial of service during the WebSocket handshake prior to the VNC client authentication.
Qemu-kvm: virtio-snd: heap buffer overflow in virtio_snd_pcm_in_cb()
A heap buffer overflow was found in the virtio-snd device in QEMU. When reading input audio in the virtio-snd input callback, virtio_snd_pcm_in_cb, the function did not check whether the iov can fit the data buffer. This issue can trigger an out-of-bounds write if the size of the virtio queue element is equal to virtio_snd_pcm_status, which makes the available space for audio data zero.
Qemu: sdhci: heap buffer overflow in sdhci_write_dataport()
A heap-based buffer overflow was found in the SDHCI device emulation of QEMU. The bug is triggered when both `s->data_count` and the size of `s->fifo_buffer` are set to 0x200, leading to an out-of-bound access. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition.
A flaw was found in QEMU, in the virtio-scsi, virtio-blk, and virtio-crypto devices. The size for virtqueue_push as set in virtio_scsi_complete_req / virtio_blk_req_complete / virito_crypto_req_complete could be larger than the true size of the data which has been sent to guest. Once virtqueue_push() finally calls dma_memory_unmap to ummap the in_iov, it may call the address_space_write function to write back the data. Some uninitialized data may exist in the bounce.buffer, leading to an information leak.
A flaw was found in QEMU. An assertion failure was present in the usb_ep_get() function in hw/net/core.c when trying to get the USB endpoint from a USB device. This flaw may allow a malicious unprivileged guest user to crash the QEMU process on the host and cause a denial of service condition.
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.
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: 9pfs: suid/sgid bits not dropped on file write
A flaw was found in the 9p passthrough filesystem (9pfs) implementation in QEMU. When a local user in the guest writes an executable file with SUID or SGID, none of these privileged bits are correctly dropped. As a result, in rare circumstances, this flaw could be used by malicious users in the guest to elevate their privileges within the guest and help a host local user to elevate privileges on the host.
An off-by-one read/write issue was found in the SDHCI device of QEMU. It occurs when reading/writing the Buffer Data Port Register in sdhci_read_dataport and sdhci_write_dataport, respectively, if data_count == block_size. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition.
Media · CVSS 4.4EPSS 0,21%Sin corrección publicada
CVE-2021-3735
A deadlock issue was found in the AHCI controller device of QEMU. It occurs on a software reset (ahci_reset_port) while handling a host-to-device Register FIS (Frame Information Structure) packet from the guest. A privileged user inside the guest could use this flaw to hang the QEMU process on the host, resulting in a denial of service condition. The highest threat from this vulnerability is to system availability.
Media · CVSS 6.5EPSS 0,31%Sin corrección publicada
CVE-2019-12067
The ahci_commit_buf function in ide/ahci.c in QEMU allows attackers to cause a denial of service (NULL dereference) when the command header 'ad->cur_cmd' is null.
A NULL pointer dereference flaw was found in the megasas-gen2 SCSI host bus adapter emulation of QEMU in versions before and including 6.0. This issue occurs in the megasas_command_cancelled() callback function while dropping a SCSI request. This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.
Media · CVSS 5.5EPSS 0,41%Sin corrección publicada
CVE-2021-20255
A stack overflow via an infinite recursion vulnerability was found in the eepro100 i8255x device emulator of QEMU. This issue occurs while processing controller commands due to a DMA reentry issue. This flaw allows a guest user or process to consume CPU cycles or crash the QEMU process on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.