CVE-2023-46842

Description

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.

How to fix CVE-2023-46842

To remediate CVE-2023-46842, upgrade the affected package to a fixed version below.

• —upgrade to 4.16.6-r0 or later
• —no fix listed

Is CVE-2023-46842 being exploited?

Low — EPSS is 2.1%, meaning exploitation activity has not been observed at scale.

Affected packages (2)

• from 0, < 4.16.6-r0
• from 0

CVSS scores

References (2)

• ADVISORYsecurity.alpinelinux.org/vuln/CVE-2023-46842
• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2023-46842