CVE-2021-27379

HIGH

Xen 3.2.0-4.11.x - Unintended DMA Access via IOMMU Update Mismanagement

Title source: llm
STIX 2.1

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.

References (4)

Core 4
Core References
Mitigation, Patch, Vendor Advisory x_refsource_confirm
http://xenbits.xen.org/xsa/advisory-366.html
Patch, Vendor Advisory x_refsource_misc
https://xenbits.xen.org/xsa/advisory-366.html
Mailing List, Third Party Advisory mailing-list x_refsource_mlist
http://www.openwall.com/lists/oss-security/2021/02/23/1
Third Party Advisory vendor-advisory x_refsource_debian
https://www.debian.org/security/2021/dsa-4888

Scores

CVSS v3 7.8
EPSS 0.0007
EPSS Percentile 21.4%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Details

Status published
Products (2)
debian/debian_linux 10.0
xen/xen 3.2.0 - 4.12.0
Published Feb 18, 2021
Tracked Since Feb 18, 2026