CVEvulnerability

CVE-2021-3308

5.5 MEDIUM Published 2021-01-26 Modified 2026-06-17 Official page ↗
Status
Modified
Published
2021-01-26
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
5.5 MEDIUM — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS 2.0 ([email protected])
4.9 MEDIUM — AV:L/AC:L/Au:N/C:N/I:N/A:C

Description

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.

Affected configurations

• xen xen (>= 4.13.1 <= 4.14.1) • xen xen 4.12.3 • xen xen 4.12.4 • fedoraproject fedora 32

References