CVE-2021-28692

Published Jun 30, 2021

Last updated 3 years ago

Overview

Description
inappropriate x86 IOMMU timeout detection / handling IOMMUs process commands issued to them in parallel with the operation of the CPU(s) issuing such commands. In the current implementation in Xen, asynchronous notification of the completion of such commands is not used. Instead, the issuing CPU spin-waits for the completion of the most recently issued command(s). Some of these waiting loops try to apply a timeout to fail overly-slow commands. The course of action upon a perceived timeout actually being detected is inappropriate: - on Intel hardware guests which did not originally cause the timeout may be marked as crashed, - on AMD hardware higher layer callers would not be notified of the issue, making them continue as if the IOMMU operation succeeded.
Source
security@xen.org
NVD status
Analyzed

Risk scores

CVSS 3.1

Type
Primary
Base score
7.1
Impact score
5.2
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Severity
HIGH

CVSS 2.0

Type
Primary
Base score
5.6
Impact score
7.8
Exploitability score
3.9
Vector string
AV:L/AC:L/Au:N/C:P/I:N/A:C

Weaknesses

nvd@nist.gov
CWE-269

Social media

Hype score
Not currently trending

Configurations