CVE-2020-15859

QEMU versión 4.2.0, presenta un uso de la memoria previamente liberada en el archivo hw/net/e1000e_core.c porque un usuario del Sistema Operativo invitado puede activar un paquete e1000e con la dirección de datos establecida en la dirección MMIO del e1000e

A use-after-free flaw was found in the INTEL 82574 NIC (e1000e) emulator of the QEMU. The issue happens while sending packets if the guest user has set the packet data address to the e1000e's MMIO address. This flaw allows a guest user or process to crash the QEMU process on the host, resulting in a denial of service.

It was discovered that QEMU incorrectly handled memory in iSCSI emulation. An attacker inside the guest could possibly use this issue to obtain sensitive information. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. Alexander Bulekov discovered that QEMU incorrectly handled Intel e1000e emulation. An attacker inside the guest could use this issue to cause QEMU to crash, resulting in a denial of service. Various other issues were also addressed.