CVE-2021-47092

In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Always clear vmx-fail on emulationrequired Revert a relatively recent change that set vmx-fail if the vCPU is in L2 and emulationrequired is true, as that behavior is completely bogus. Setting vmx-fail and synthesizing ...

UBUNTU-CVE-2021-47092

In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Always clear vmx-fail on emulationrequired Revert a relatively recent change that set vmx-fail if the vCPU is in L2 and emulationrequired is true, as that behavior is completely bogus. Setting vmx-fail and synthesizing ...

PT-2025-37650

Name of the Vulnerable Software and Affected Versions Linux kernel affected versions not specified Description The Linux kernel contains a flaw within the KVM nested virtualization implementation. Specifically, the code incorrectly loads the Time Stamp Counter TSC multiplier for L1 based on L1...

kernel: KVM: nVMX: missing IBPB when exiting from nested guest can lead to Spectre v2 attacks

A flaw was found in the KVM's Intel nested virtualization feature nVMX. Since L1 and L2 shared branch prediction modes guest-user and guest-kernel, KVM did not protect indirect branches in L1 from steering by a malicious agent in L2. This could allow a malicious nested guest to carry out Spectre ...

SUSE CVE-2011-1780

The instruction emulation in Xen 3.0.3 allows local SMP guest users to cause a denial of service host crash by replacing the instruction that causes the VM to exit in one thread with a different instruction in a different thread...

hw: cpu: Intel: Post-barrier Return Stack Buffer Predictions

A flaw was found in hw. In certain processors with Intel's Enhanced Indirect Branch Restricted Speculation eIBRS capabilities, soon after VM exit or IBPB command event, the linear address following the most recent near CALL instruction prior to a VM exit may be used as the Return Stack Buffer RSB...

hw: cpu: Intel: Post-barrier Return Stack Buffer Predictions

A flaw was found in hw. In certain processors with Intel's Enhanced Indirect Branch Restricted Speculation eIBRS capabilities, soon after VM exit or IBPB command event, the linear address following the most recent near CALL instruction prior to a VM exit may be used as the Return Stack Buffer RSB...

hw: cpu: Intel: Post-barrier Return Stack Buffer Predictions

A flaw was found in hw. In certain processors with Intel's Enhanced Indirect Branch Restricted Speculation eIBRS capabilities, soon after VM exit or IBPB command event, the linear address following the most recent near CALL instruction prior to a VM exit may be used as the Return Stack Buffer RSB...

DEBIAN-CVE-2021-4093

A flaw was found in the KVM's AMD code for supporting the Secure Encrypted Virtualization-Encrypted State SEV-ES. A KVM guest using SEV-ES can trigger out-of-bounds reads and writes in the host kernel via a malicious VMGEXIT for a string I/O instruction for example, outs or ins using the exit...

Unbreakable Enterprise kernel security update

4.1.12-124.36.4 - KVM: nVMX: Check IO instruction VM-exit conditions Oliver Upton Orabug: 30944739 CVE-2020-2732 - KVM: nVMX: Refactor IO bitmap checks into helper function Oliver Upton Orabug: 30944739 CVE-2020-2732 - KVM: nVMX: Don't emulate instructions in guest mode Paolo Bonzini Orabug:...

Unbreakable Enterprise kernel security update

4.1.12-124.36.1.1 - KVM: nVMX: Check IO instruction VM-exit conditions Oliver Upton Orabug: 30847137 CVE-2020-2732 - KVM: nVMX: Refactor IO bitmap checks into helper function Oliver Upton Orabug: 30847137 CVE-2020-2732 - KVM: nVMX: Dont emulate instructions in guest mode Paolo Bonzini Orabug:...

CVE-2019-7221

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...

UBUNTU-CVE-2018-12904

In arch/x86/kvm/vmx.c in the Linux kernel before 4.17.2, when nested virtualization is used, local attackers could cause L1 KVM guests to VMEXIT, potentially allowing privilege escalations and denial of service attacks due to lack of checking of CPL...

KVM (Nested Virtualization) - L1 Guest Privilege Escalation Vulnerability

Exploit for linux platform in category dos / poc When KVM on Intel virtualizes another hypervisor as L1 VM it does not verify that VMX instructions from the L1 VM which trigger a VM exit and are emulated by L0 KVM are coming from ring 0. For code running on bare metal or VMX root mode this is...

KVM (Nested Virtualization) - L1 Guest Privilege Escalation

KVM Nested Virtualization - L1 Guest Privilege Escalation When KVM on Intel virtualizes another hypervisor as L1 VM it does not verify that VMX instructions from the L1 VM which trigger a VM exit and are emulated by L0 KVM are coming from ring 0. For code running on bare metal or VMX root mode th...

KVM (Nested Virtualization) - L1 Guest Privilege Escalation

When KVM on Intel virtualizes another hypervisor as L1 VM it does not verify that VMX instructions from the L1 VM which trigger a VM exit and are emulated by L0 KVM are coming from ring 0. For code running on bare metal or VMX root mode this is enforced by hardware. However, for code running in L...

Updated kernel-tmb packages fix security vulnerabilities

This kernel-tmb update is based on the upstream 4.14.13 and fixes several security issues. The most important fix in this update is for the security issue named "Meltdown" that is fixed in theese kernels by enabling kernel Page Table Isolation KTPI. Note that according to AMD, this issue does not...

kernel: kvm: vmx: invept vm exit not handled

It was found that the Linux kernel's KVM subsystem did not handle the VM exits gracefully for the invept Invalidate Translations Derived from EPT instructions. On hosts with an Intel processor and invept VM exit support, an unprivileged guest user could use these instructions to crash the guest...

RHEL 6 : kernel (RHSA-2014:1843)

The remote Redhat Enterprise Linux 6 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2014:1843 advisory. The kernel packages contain the Linux kernel, the core of any Linux operating system. A race condition flaw was found in the way the Linux...

kernel: kvm: vmx: invvpid vm exit not handled

It was found that the Linux kernel's KVM subsystem did not handle the VM exits gracefully for the invvpid Invalidate Translations Based on VPID instructions. On hosts with an Intel processor and invppid VM exit support, an unprivileged guest user could use these instructions to crash the guest...