CVE-2021-28705

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

24/11/2021

Last modified:

04/02/2024

Description

issues with partially successful P2M updates on x86 T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] x86 HVM and PVH guests may be started in populate-on-demand (PoD) mode, to provide a way for them to later easily have more memory assigned. Guests are permitted to control certain P2M aspects of individual pages via hypercalls. These hypercalls may act on ranges of pages specified via page orders (resulting in a power-of-2 number of pages). In some cases the hypervisor carries out the requests by splitting them into smaller chunks. Error handling in certain PoD cases has been insufficient in that in particular partial success of some operations was not properly accounted for. There are two code paths affected - page removal (CVE-2021-28705) and insertion of new pages (CVE-2021-28709). (We provide one patch which combines the fix to both issues.)

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 7.80 HIGH
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): High
Availability (A): High

Base Score 3.x

7.80

Severity 3.x

HIGH

Vector 2.0

AV:L/AC:M/Au:N/C:C/I:C/A:C CVSS v2.0 Severity and Metrics:

Base Score: 6.90 MEDIUM
Vector: AV:L/AC:M/Au:N/C:C/I:C/A:C

Attack Vector (AV): Local
Attack Complexity (AC): Medium
Authentication (Au): None
Confidentiality (C): Complete
Integrity (I): Complete
Availability (A): Complete

Base Score 2.0

6.90

Severity 2.0

MEDIUM

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:o:xen:xen:::::::x86:*	3.4.0 (including)	4.12.4 (including)
cpe:2.3:o:xen:xen:::::::x86:*	4.13.0 (including)	4.13.4 (including)
cpe:2.3:o:xen:xen:::::::x86:*	4.14.0 (including)	4.14.3 (including)
cpe:2.3:o:xen:xen:4.15.0::::::x86:
cpe:2.3:o:xen:xen:4.15.1::::::x86:
cpe:2.3:o:fedoraproject:fedora:34:::::::*
cpe:2.3:o:fedoraproject:fedora:35:::::::*
cpe:2.3:o:debian:debian_linux:11.0:::::::*

To consult the complete list of CPE names with products and versions, see this page

CVE-2021-28705

Description

Impact

Vulnerable products and versions

References to Advisories, Solutions, and Tools