CVE-2021-28706 Information

Description

guests may exceed their designated memory limit When a guest is permitted to have close to 16TiB of memory it may be able to issue hypercalls to increase its memory allocation beyond the administrator established limit. This is a result of a calculation done with 32-bit precision which may overflow. It would then only be the overflowed (and hence small) number which gets compared against the established upper bound.

CVSS Vector

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

Reference

https://xenbits.xenproject.org/xsa/advisory-385.txt https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/I7ZGWVVRI4XY2XSTBI3XEMWBXPDVX6OT/ https://www.debian.org/security/2021/dsa-5017 https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PXUI4VMD52CH3T7YXAG3J2JW7ZNN3SXF/

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

CHANGED

Integrity Impact

NONE

Availability Impact

NONE

Base Score

HIGH

Base Severity

8.6