CVE-2021-26933

Common vulnerabilities & exposures (CVE)

CVE database CVE database blogpost Release & EoL database

Published at: - 17-02-2021 03:15

Last modified: - 27-05-2022 07:00

Total changes: - 4

Description

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.

Common Vulnerability Scoring System (CVSS)

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

Low

Attack complexity

Local

Attack vector

None

Availability

High

Confidentiality

None

Integrity

Low

Privileges required

Unchanged

Scope

None

User interaction

5.5

Base score

1.8

3.6

Exploitability score

Impact score

Verification logic

vendor=xen AND product=xen AND target_hardware=arm AND versionEndIncluding=4.14.1 AND versionStartIncluding=4.9.0

vendor=fedoraproject AND product=fedora AND version=32

vendor=fedoraproject AND product=fedora AND version=33

vendor=Debian AND product=debian_linux AND version=10.0

Reference

http://xenbits.xen.org/xsa/advisory-364.html
FEDORA-2021-47f53a940a-Mailing List, Third Party Advisory
FEDORA-2021-4c819bf1ad-Mailing List, Third Party Advisory
DSA-4888-Third Party Advisory

Keywords

CVE-2021-26933

Common vulnerabilities & exposures (CVE)

Description

Common Vulnerability Scoring System (CVSS)

Verification logic

Reference

NVD

CVE-2021-26933

CVE

Common vulnerabilities & exposures

CVSS

Common vulnerability scoring system

Security

Vulnerabilities

Exposures