USN-4300-1 linux, linux-aws, linux-gcp, linux-gcp-5.3, linux-gke-5.3, linux-hwe, linux-kvm, linux-oracle, linux-raspi2, linux-raspi2-5.3, linux-azure, linux-azure-5.3 vulnerabilities

It was discovered that the KVM implementation in the Linux kernel, when paravirtual TLB flushes are enabled in guests, the hypervisor in some situations could miss deferred TLB flushes or otherwise mishandle them. An attacker in a guest VM could use this to expose sensitive information read memor...

Important: kernel

Issue Overview: A stack buffer overflow issue was found in the getrawsocket routine of the Host kernel accelerator for virtio net vhost-net driver. It could occur while doing an ictolVHOSTNETSETBACKEND call, and retrieving socket name in a kernel stack variable via getrawsocket. A user able to...

MGASA-2020-0110 Updated kernel packages fix security vulnerability

This update is based on upstream 5.5.6 and fixes at least the following security vulnerability: A flaw was found in the way KVM hypervisor handled instruction emulation for the L2 guest when nested=1 virtualization is enabled. In the instruction emulation, the L2 guest could trick the L0 hypervis...

Oracle Linux 6 / 7 : Unbreakable Enterprise kernel (ELSA-2020-5542)

The remote Oracle Linux 6 / 7 host has packages installed that are affected by a vulnerability as referenced in the ELSA-2020-5542 advisory. - KVM: nVMX: Check IO instruction VM-exit conditions Oliver Upton Orabug: 30847137 CVE-2020-2732 - KVM: nVMX: Refactor IO bitmap checks into helper function...

CVE-2020-2732

A flaw was found in the way KVM hypervisor handled instruction emulation for the L2 guest when nested=1 virtualization is enabled. In the instruction emulation, the L2 guest could trick the L0 hypervisor into accessing sensitive bits of the L1 hypervisor. An L2 guest could use this flaw to...

UBUNTU-CVE-2020-2732

A flaw was discovered in the way that the KVM hypervisor handled instruction emulation for an L2 guest when nested virtualisation is enabled. Under some circumstances, an L2 guest may trick the L0 guest into accessing sensitive L1 resources that should be inaccessible to the L2 guest...

Virtuozzo 7 : readykernel-patch (VZA-2019-045)

According to the version of the vzkernel package and the readykernel-patch installed, the Virtuozzo installation on the remote host is affected by the following vulnerabilities : - A use-after-free vulnerability was found in the way KVM implements its device control API. When a device is created...

Huawei EulerOS: Security Advisory for kernel (EulerOS-SA-2019-1486)

The remote host is missing an update for the Huawei EulerOS SPDX-FileCopyrightText: 2020 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

Huawei EulerOS: Security Advisory for kernel (EulerOS-SA-2019-1076)

The remote host is missing an update for the Huawei EulerOS SPDX-FileCopyrightText: 2020 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

Huawei EulerOS: Security Advisory for kvm (EulerOS-SA-2019-1370)

The remote host is missing an update for the Huawei EulerOS SPDX-FileCopyrightText: 2020 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

Kernel: KVM: nVMX: use-after-free of the hrtimer for emulation of the preemption timer

A use-after-free vulnerability was found in the way the Linux kernel's KVM hypervisor emulates a preemption timer for L2 guests when nested =1 virtualization is enabled. This high resolution timerhrtimer runs when a L2 guest is active. After VM exit, the syncvmcs12 timer object is stopped. The...

Kernel: KVM: nVMX: use-after-free of the hrtimer for emulation of the preemption timer

A use-after-free vulnerability was found in the way the Linux kernel's KVM hypervisor emulates a preemption timer for L2 guests when nested =1 virtualization is enabled. This high resolution timerhrtimer runs when a L2 guest is active. After VM exit, the syncvmcs12 timer object is stopped. The...

Kernel: KVM: nVMX: guest accesses L0 MSR causes potential DoS

A flaw was found in the way KVM hypervisor handled x2APIC Machine Specific Register 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 th...

Kernel: KVM: nVMX: guest accesses L0 MSR causes potential DoS

A flaw was found in the way KVM hypervisor handled x2APIC Machine Specific Register 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 th...

NewStart CGSL CORE 5.05 / MAIN 5.05 : kernel Multiple Vulnerabilities (NS-SA-2019-0085)

The remote NewStart CGSL host, running version CORE 5.05 / MAIN 5.05, has kernel packages installed that are affected by multiple vulnerabilities: - A use-after-free vulnerability was found in the way the Linux kernel's KVM hypervisor emulates a preemption timer for L2 guests when nested =1...

User-After-Free

Linux kernel is vulnerable to use-after-free attacks. This is because the way the Linux kernel's KVM hypervisor emulates a preemption timer for L2 guests when nested =1 virtualization is enabled. An attacker could use this flaw to crash the host kernel resulting in a denial of service or...

Ubuntu 19.04 : Linux kernel vulnerabilities (USN-3979-1) (MDSUM/RIDL) (MFBDS/RIDL/ZombieLoad) (MLPDS/RIDL) (MSBDS/Fallout)

Ke Sun, Henrique Kawakami, Kekai Hu, Rodrigo Branco, Giorgi Maisuradze, Dan Horea Lutas, Andrei Lutas, Volodymyr Pikhur, Stephan van Schaik, Alyssa Milburn, Sebastian Osterlund, Pietro Frigo, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida, Moritz Lipp, Michael Schwarz, and Daniel Gruss discovered...

Kernel: KVM: nVMX: use-after-free of the hrtimer for emulation of the preemption timer

A use-after-free vulnerability was found in the way the Linux kernel's KVM hypervisor emulates a preemption timer for L2 guests when nested =1 virtualization is enabled. This high resolution timerhrtimer runs when a L2 guest is active. After VM exit, the syncvmcs12 timer object is stopped. The...

Kernel: KVM: nVMX: use-after-free of the hrtimer for emulation of the preemption timer

A use-after-free vulnerability was found in the way the Linux kernel's KVM hypervisor emulates a preemption timer for L2 guests when nested =1 virtualization is enabled. This high resolution timerhrtimer runs when a L2 guest is active. After VM exit, the syncvmcs12 timer object is stopped. The...

AZL-6521 CVE-2019-3887 affecting package kernel for versions less than 5.10.78.1-1

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 t...