description: A flaw was found in the way KVM hypervisor handled x2APIC Machine Specific Rregister (MSR) access with nested(=1) virtualization enabled. In that, L1 guest could access L0's APIC register values via L2 guest, when 'virtualize x2APIC mode' is enabled. A guest could use this flaw to potentially crash the host kernel resulting in DoS issue. Kernel versions from 4.16 and newer are vulnerable to this issue.
problem types: CWE-863
affected:
{
vendor: The Linux Foundation
product: Kernel
versions:
version: from 4.16, status: affected
}
metrics:
cvssV3_0: [
version: 3.0
vectorString: CVSS:3.0/AV:L/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:H
attackVector: LOCAL
attackComplexity: HIGH
privilegesRequired: HIGH
userInteraction: NONE
scope: CHANGED
confidentialityImpact: LOW
integrityImpact: LOW
availabilityImpact: HIGH
baseScore: 6.7
baseSeverity: MEDIUM
]