CVE-2021-27379 Information

Description

An issue was discovered in Xen through 4.11.x allowing x86 Intel HVM guest OS users to achieve unintended read/write DMA access and possibly cause a denial of service (host OS crash) or gain privileges. This occurs because a backport missed a flush and thus IOMMU updates were not always correct. NOTE: this issue exists because of an incomplete fix for CVE-2020-15565.

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Reference

https://xenbits.xen.org/xsa/advisory-366.html http://www.openwall.com/lists/oss-security/2021/02/23/1 http://xenbits.xen.org/xsa/advisory-366.html https://www.debian.org/security/2021/dsa-4888

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

7.8