CVE-2018-17962

Qemu tiene un desbordamiento de búfer en pcnet_receive en hw/net/pcnet.c debido a que se emplea un tipo de datos de enteros incorrecto.

An integer overflow issue was found in the AMD PC-Net II NIC emulation in QEMU. It could occur while receiving packets, if the size value was greater than INT_MAX. Such overflow would lead to stack buffer overflow issue. A user inside guest could use this flaw to crash the QEMU process resulting in DoS.

Daniel Shapira and Arash Tohidi discovered that QEMU incorrectly handled NE2000 device emulation. An attacker inside the guest could use this issue to cause QEMU to crash, resulting in a denial of service. It was discovered that QEMU incorrectly handled the Slirp networking back-end. A privileged attacker inside the guest could use this issue to cause QEMU to crash, resulting in a denial of service, or possibly execute arbitrary code on the host. In the default installation, when QEMU is used with libvirt, attackers would be isolated by the libvirt AppArmor profile. This issue only affected Ubuntu 14.04 LTS, Ubuntu 16.04 LTS and Ubuntu 18.04 LTS. Various other issues were also addressed.