CVE-2021-26933

An issue was discovered in Xen 4.9 through 4.14.x. On Arm, a guest is allowed to control whether memory accesses are bypassing the cache. This means that Xen needs to ensure that all writes (such as the ones during scrubbing) have reached the memory before handing over the page to a guest. Unfortunately, the operation to clean the cache is happening before checking if the page was scrubbed. Therefore there is no guarantee when all the writes will reach the memory.

CVSS v3.0 5.5 MEDIUM
CVSS v2.0 2.1 LOW

5.5^/10

CVSS v3.0 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

2.1^/10

CVSS v2.0 : LOW

Vector : AV:L/AC:L/Au:N/C:P/I:N/A:N

Exploitability : 3.9 / Impact : 2.9

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

References

Link	Resource
http://xenbits.xen.org/xsa/advisory-364.html	Patch Vendor Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/EOAJBVAVR6RSCUCHNXPVSNRPSFM7INMP/	Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4GELN5E6MDR5KQBJF5M5COUUED3YFZTD/	Mailing List Third Party Advisory
https://www.debian.org/security/2021/dsa-4888	Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:o:xen:xen:*:*:*:*:*:*:arm:*

Configuration 2 (hide)

OR	cpe:2.3:o:fedoraproject:fedora:32:::::::*
	cpe:2.3:o:fedoraproject:fedora:33:::::::*

Configuration 3 (hide)

cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

Information

Published : 2021-02-16 18:15

Updated : 2022-05-27 10:00

NVD link : CVE-2021-26933

Mitre link : CVE-2021-26933

JSON object : View

CWE

NVD-CWE-noinfo

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Products Affected

debian

debian_linux

xen

xen

fedoraproject

fedora

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