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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| The Linux Foundation | Kernel | from 4.16 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 4.19.37-1 | — |
| Debian 13 | linux | 4.19.37-1 | — |
| Debian 12 | linux | 4.19.37-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | linux-azure | 4.18.0-1018.18~18.04.1 | USN-3980-2 |
| Ubuntu 18.04 LTS | linux-gcp-edge | 4.18.0-1011.12~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-hwe | 4.18.0-20.21~18.04.1 | USN-3980-2 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | kernel-rt +12 | 4.18.0-80.11.1.rt9.156.el8_0 | RHSA-2019:2741 |
| RHEL 8 | perf +28 | 4.18.0-80.11.1.el8_0 | RHSA-2019:2703 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | kernel-source | 5.14.6-1.4 | openSUSE-SU-2024:13704-1, openSUSE-SU-2024:10728-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | kernel | 6.6.35.1-4 | — |
| Azure Linux 2 (CBL-Mariner) | kernel | 5.10.78.1-1 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | perf +19 | 4.18.0-80.11.1.el8_0 | ELSA-2019-2703 |
Advisories 6
- RHSA-2019:2741 Red Hat Security Advisory: kernel-rt security and bug fix update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- RHSA-2019:2703 Red Hat Security Advisory: kernel security and bug fix update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- USN-3980-2 linux-hwe, linux-azure vulnerabilities Ubuntu Security Notices (USN) · Jun 1, 2026
- openSUSE-SU-2024:13704-1 kernel-devel-longterm-6.6.17-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10728-1 kernel-devel-5.14.6-1.4 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- ELSA-2019-2703 Important: kernel security and bug fix update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Sep 12, 2019
References
- 107850 vdb-entry
- FEDORA-2019-94dc902948 vendor-advisory
- USN-3980-1 vendor-advisory
- USN-3979-1 vendor-advisory
- USN-3980-2 vendor-advisory
- RHSA-2019:2703 vendor-advisory
- RHSA-2019:2741 vendor-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3887