xen/arm: No memory limit for dom0less domUs

2021-08-2512:00:00

Xen Project

xenbits.xen.org

4.9 Medium

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

HIGH

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

HIGH

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

6.8 Medium

CVSS2

Access Vector

NETWORK

Access Complexity

LOW

Authentication

SINGLE

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

COMPLETE

AV:N/AC:L/Au:S/C:N/I:N/A:C

0.004 Low

EPSS

Percentile

74.3%

JSON

ISSUE DESCRIPTION

The dom0less feature allows an administrator to create multiple unprivileged domains directly from Xen. Unfortunately, the memory limit from them is not set. This allow a domain to allocate memory beyond what an administrator originally configured.

IMPACT

Malicious dom0less guest could drive Xen out of memory and may result to a Denial of Service (DoS) attack affecting the entire system.

VULNERABLE SYSTEMS

Only Arm systems are vulnerable. Only domains created using the dom0less feature are affected.
Only domains created using the dom0less feature can leverage the vulnerability.
All versions of Xen since 4.12 are vulnerable.