CVE-2019-3887 is a medium-severity vulnerability affecting KVM hypervisors in Linux kernels version 4.16 and newer, specifically impacting Canonical, Fedora, and Red Hat distributions. This flaw allows a malicious L2 guest to access L0's APIC register values through an L1 guest when nested virtualization and virtualized x2APIC mode are enabled. The attack requires local access to the guest and has high attack complexity, but can lead to a denial-of-service by crashing the host kernel. There is no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage regarding this vulnerability.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
>= 4.16CPE matchmatch criteria | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | ||
29CPE matchmatch criteria | cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:* | ||
18.04CPE matchmatch criteria | cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* | ||
18.10CPE matchmatch criteria | cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:* | ||
19.04CPE matchmatch criteria | cpe:2.3:o:canonical:ubuntu_linux:19.04:*:*:*:*:*:*:* |
CVSS version used by this source: 3.0
CVSS:3.0/AV:L/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:H
The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.1 Bluesky, 0.0 Mastodon, and 0.1 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.4 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
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.
Apr 9, 2019Kernel: KVM: nVMX: guest accesses L0 MSR causes potential DoS
Apr 5, 2019