CVE-2020-25604

Published Sep 23, 2020

Last updated a year ago

Overview

Description
An issue was discovered in Xen through 4.14.x. There is a race condition when migrating timers between x86 HVM vCPUs. When migrating timers of x86 HVM guests between its vCPUs, the locking model used allows for a second vCPU of the same guest (also operating on the timers) to release a lock that it didn't acquire. The most likely effect of the issue is a hang or crash of the hypervisor, i.e., a Denial of Service (DoS). All versions of Xen are affected. Only x86 systems are vulnerable. Arm systems are not vulnerable. Only x86 HVM guests can leverage the vulnerability. x86 PV and PVH cannot leverage the vulnerability. Only guests with more than one vCPU can exploit the vulnerability.
Source
cve@mitre.org
NVD status
Modified

Risk scores

CVSS 3.1

Type
Primary
Base score
4.7
Impact score
3.6
Exploitability score
1
Vector string
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

CVSS 2.0

Type
Primary
Base score
1.9
Impact score
2.9
Exploitability score
3.4
Vector string
AV:L/AC:M/Au:N/C:N/I:N/A:P

Weaknesses

nvd@nist.gov
CWE-362

Social media

Hype score
Not currently trending

Configurations