CVE-2023-46842

Unlike 32-bit PV guests, HVM guests may switch freely between 64-bit and other modes. This in particular means that they may set registers used to pass 32-bit-mode hypercall arguments to values outside of the range 32-bit code would be able to set them to. When processing of hypercalls takes a considerable amount of time, the hypervisor may choose to invoke a hypercall continuation. Doing so involves putting (perhaps updated) hypercall arguments in respective registers. For guests not running in 64-bit mode this further involves a certain amount of translation of the values. Unfortunately internal sanity checking of these translated values assumes high halves of registers to always be clear when invoking a hypercall. When this is found not to be the case, it triggers a consistency check in the hypervisor and causes a crash.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.0 / Impact : 4.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://xenbits.xenproject.org/xsa/advisory-454.html	Patch Vendor Advisory
http://xenbits.xen.org/xsa/advisory-454.html	Patch Vendor Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/D5OK6MH75S7YWD34EWW7QIZTS627RIE3/	Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/RYAZ7P6YFJ2E3FHKAGIKHWS46KYMMTZH/	Mailing List Third Party Advisory
https://xenbits.xenproject.org/xsa/advisory-454.html	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

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

Configuration 2 (hide)

OR	cpe:2.3:o:fedoraproject:fedora:38:::::::*
	cpe:2.3:o:fedoraproject:fedora:40:::::::*

History

No history.

Information

Published : 2024-05-16 14:15

Updated : 2026-01-05 19:05

NVD link : CVE-2023-46842

Mitre link : CVE-2023-46842

CVE.ORG link : CVE-2023-46842

JSON object : View

Products Affected

xen

xen

fedoraproject

fedora

CWE

CWE-843

Access of Resource Using Incompatible Type ('Type Confusion')

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