CVE-2020-1983

Una vulnerabilidad de uso de la memoria previamente liberada en la función ip_reass() en el archivo ip_input.c de libslirp versiones 4.2.0 y anteriores permite que paquetes especialmente diseñados causen una denegación de servicio.

A use-after-free flaw was found in the SLiRP networking implementation of the QEMU emulator. Specifically, this flaw occurs in the ip_reass() routine while reassembling incoming IP fragments whose combined size is bigger than 65k. This flaw allows an attacker to crash the QEMU process on the host, resulting in a denial of service.

It was discovered that QEMU incorrectly handled bochs-display devices. A local attacker in a guest could use this to cause a denial of service or possibly execute arbitrary code in the host. This issue only affected Ubuntu 19.10. It was discovered that QEMU incorrectly handled memory during certain VNC operations. A remote attacker could possibly use this issue to cause QEMU to consume resources, resulting in a denial of service. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 19.10. Various other issues were also addressed.