CVE-2021-3308

Published: 26 January 2021

An issue was discovered in Xen 4.12.3 through 4.12.4 and 4.13.1 through 4.14.x. An x86 HVM guest with PCI pass through devices can force the allocation of all IDT vectors on the system by rebooting itself with MSI or MSI-X capabilities enabled and entries setup. Such reboots will leak any vectors used by the MSI(-X) entries that the guest might had enabled, and hence will lead to vector exhaustion on the system, not allowing further PCI pass through devices to work properly. HVM guests with PCI pass through devices can mount a Denial of Service (DoS) attack affecting the pass through of PCI devices to other guests or the hardware domain. In the latter case, this would affect the entire host.

Priority

Medium

CVSS 3 base score: 5.5

Status

Package Release Status
xen
Launchpad, Ubuntu, Debian
Upstream Needs triage

Ubuntu 20.10 (Groovy Gorilla) Not vulnerable
(4.11.4+24-gddaaccbbab-1ubuntu2)
Ubuntu 20.04 LTS (Focal Fossa) Not vulnerable
(4.11.3+24-g14b62ab3e5-1ubuntu2)
Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(4.9.2-0ubuntu1)
Ubuntu 16.04 ESM (Xenial Xerus) Not vulnerable
(4.6.5-0ubuntu1.4)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Binaries built from this source package are in Universe and so are supported by the community.