CVE-2022-48793

2024-07-1612:15:04

Google

osv.dev

linux kernel

kvm

x86

null derefernce

nested migration

npt

guest memory

CVSS3

5.5

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

HIGH

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

AI Score

Confidence

High

EPSS

Percentile

5.0%

JSON

In the Linux kernel, the following vulnerability has been resolved:

KVM: x86: nSVM: fix potential NULL derefernce on nested migration

Turns out that due to review feedback and/or rebases
I accidentally moved the call to nested_svm_load_cr3 to be too early,
before the NPT is enabled, which is very wrong to do.

KVM can’t even access guest memory at that point as nested NPT
is needed for that, and of course it won’t initialize the walk_mmu,
which is main issue the patch was addressing.

Fix this for real.