title: Speculative execution attacks in KVM VMX
description: A regression exists in the Linux Kernel within KVM: nVMX that allowed for speculative execution attacks. L2 can carry out Spectre v2 attacks on L1 due to L1 thinking it doesn't need retpolines or IBPB after running L2 due to KVM (L0) advertising eIBRS support to L1. An attacker at L2 with code execution can execute code on an indirect branch on the host machine. We recommend upgrading to Kernel 6.2 or past commit 2e7eab81425a
problem types: CWE-1188 Insecure Default Initialization of Resource
affected:
{
defaultStatus: unaffected
packageName: KVM
product: Linux Kernel
repo: https://git.kernel.org/
vendor: Linux
versions:
lessThan: 2e7eab81425a, status: affected, version: 0, versionType: git
lessThan: 6.2, status: affected, version: 0, versionType: custom
}
metrics:
cvssV3_1: [
attackComplexity: HIGH
attackVector: LOCAL
availabilityImpact: LOW
baseScore: 5.8
baseSeverity: MEDIUM
confidentialityImpact: LOW
integrityImpact: HIGH
privilegesRequired: LOW
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:L
version: 3.1
]
format: CVSS
scenarios: GENERAL