hw/net/xgmac.c in the XGMAC Ethernet controller in QEMU before 07-20-2020 has a buffer overflow. This occurs during packet transmission and affects the highbank and midway emulated machines. A guest user or process could use this flaw to crash the QEMU process on the host, resulting in a denial of service or potential privileged code execution. This was fixed in commit 5519724a13664b43e225ca05351c60b4468e4555.
An assertion failure issue was found in the Network Block Device(NBD) Server in all QEMU versions before QEMU 5.0.1. This flaw occurs when an nbd-client sends a spec-compliant request that is near the boundary of maximum permitted request length. A remote nbd-client could use this flaw to crash the qemu-nbd server resulting in a denial of service.
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.
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.
In QEMU 5.0.0 and earlier, es1370_transfer_audio in hw/audio/es1370.c does not properly validate the frame count, which allows guest OS users to trigger an out-of-bounds access during an es1370_write() operation.
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.
The process_tx_desc function in hw/net/e1000.c in QEMU before 2.4.0.1 does not properly process transmit descriptor data when sending a network packet, which allows attackers to cause a denial of service (infinite loop and guest crash) via unspecified vectors.
Buffer overflow in the send_control_msg function in hw/char/virtio-serial-bus.c in QEMU before 2.4.0 allows guest users to cause a denial of service (QEMU process crash) via a crafted virtio control message.