CVE-2021-28710

certain VT-d IOMMUs may not work in shared page table mode For efficiency reasons, address translation control structures (page tables) may (and, on suitable hardware, by default will) be shared between CPUs, for second-level translation (EPT), and IOMMUs. These page tables are presently set up to always be 4 levels deep. However, an IOMMU may require the use of just 3 page table levels. In such a configuration the lop level table needs to be stripped before inserting the root table's address into the hardware pagetable base register. When sharing page tables, Xen erroneously skipped this stripping. Consequently, the guest is able to write to leaf page table entries.

CVSS v3.0 8.8 HIGH
CVSS v2.0 6.9 MEDIUM

8.8^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 2.0 / Impact : 6.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

6.9^/10

CVSS v2.0 : MEDIUM

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

Exploitability : 3.4 / Impact : 10.0

Access Vector LOCAL

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://xenbits.xenproject.org/xsa/advisory-390.txt	Vendor Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/I7ZGWVVRI4XY2XSTBI3XEMWBXPDVX6OT/	Mailing List Third Party Advisory
https://security.gentoo.org/glsa/202208-23

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Configurations

Configuration 1 (hide)

cpe:2.3:o:xen:xen:4.15.0:*:*:*:*:*:x86:*

Configuration 2 (hide)

cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*

Information

Published : 2021-11-21 07:15

Updated : 2022-08-15 04:15

NVD link : CVE-2021-28710

Mitre link : CVE-2021-28710

JSON object : View

CWE

CWE-269

Improper Privilege Management

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Products Affected

xen

xen

fedoraproject

fedora

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