Spectre v2 SMT mitigations problem in Linux kernel

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Important: kernel

Issue Overview: 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 L...

The vulnerability of the spectre_v2_select_mitigation() function in the Linux operating system allows a hacker to execute arbitrary code.

The vulnerability of the spectrev2selectmitigation function in the Linux operating system is related to errors in Intel processors when processing the RET instruction after the termination of a virtual machine. Exploiting this vulnerability allows an attacker to execute arbitrary code...

SUSE CVE-2018-15572

The spectrev2selectmitigation function in arch/x86/kernel/cpu/bugs.c in the Linux kernel before 4.18.1 does not always fill RSB upon a context switch, which makes it easier for attackers to conduct userspace-userspace spectreRSB attacks...

SUSE CVE-2020-10767

A flaw was found in the Linux kernel before 5.8-rc1 in the implementation of the Enhanced IBPB Indirect Branch Prediction Barrier. The IBPB mitigation will be disabled when STIBP is not available or when the Enhanced Indirect Branch Restricted Speculation IBRS is available. This flaw allows a loc...

AZL-12951 CVE-2022-2196 affecting package kernel for versions less than 5.15.102.1-1

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...

UBUNTU-CVE-2021-28689

x86: Speculative vulnerabilities with bare non-shim 32-bit PV guests 32-bit x86 PV guest kernels run in ring 1. At the time when Xen was developed, this area of the i386 architecture was rarely used, which is why Xen was able to use it to implement paravirtualisation, Xen's novel approach to...

The vulnerability of the spectre_v2_select_mitigation function in the Linux operating system, related to out-of-buffer reading, allows attackers to access confidential data.

The vulnerability of the spectrev2selectmitigation function in the Linux operating system is related to incorrect filling of the RSB when switching contexts. Exploiting this vulnerability can allow an attacker to gain access to confidential data...

PT-2021-3505 · Xen +2 · Xen +2

Name of the Vulnerable Software and Affected Versions: Xen affected versions not specified Description: The issue is related to the implementation of paravirtualization PV mode in the Xen hypervisor, specifically with the use of the Indirect Branch Restricted Speculation IBRS mechanism. This coul...

A flaw was found in the Linux kernel before 5.8-rc1 in the implementation of the Enhanced IBPB (Indirect Branch Prediction Barrier). The IBPB mitigation will be disabled when STIBP is not available or when the Enhanced Indirect Branch Restricted Speculation (IBRS) is available. This flaw allows a local attacker to perform a Spectre V2 style attack when this configuration is active. The highest threat from this vulnerability is to confidentiality.

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A flaw was found in the Linux Kernel before 5.8-rc1 in the prctl() function where it can be used to enable indirect branch speculation after it has been disabled. This call incorrectly reports it as being 'force disabled' when it is not and opens the system to Spectre v2 attacks. The highest threat from this vulnerability is to confidentiality.

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DEBIAN-CVE-2020-10768

A flaw was found in the Linux Kernel before 5.8-rc1 in the prctl function, where it can be used to enable indirect branch speculation after it has been disabled. This call incorrectly reports it as being 'force disabled' when it is not and opens the system to Spectre v2 attacks. The highest threa...

DEBIAN-CVE-2020-10767

A flaw was found in the Linux kernel before 5.8-rc1 in the implementation of the Enhanced IBPB Indirect Branch Prediction Barrier. The IBPB mitigation will be disabled when STIBP is not available or when the Enhanced Indirect Branch Restricted Speculation IBRS is available. This flaw allows a loc...

kernel: Indirect branch speculation can be enabled after it was force-disabled by the PR_SPEC_FORCE_DISABLE prctl command.

A flaw was found in the prctl function, where it can be used to enable indirect branch speculation after it has been disabled. This call incorrectly reports it as being 'force disabled' when it is not and opens the system to Spectre v2 attacks. The highest threat from this vulnerability is to...

kernel: Indirect branch speculation can be enabled after it was force-disabled by the PR_SPEC_FORCE_DISABLE prctl command.

A flaw was found in the prctl function, where it can be used to enable indirect branch speculation after it has been disabled. This call incorrectly reports it as being 'force disabled' when it is not and opens the system to Spectre v2 attacks. The highest threat from this vulnerability is to...

kernel: Indirect branch speculation can be enabled after it was force-disabled by the PR_SPEC_FORCE_DISABLE prctl command.

A flaw was found in the prctl function, where it can be used to enable indirect branch speculation after it has been disabled. This call incorrectly reports it as being 'force disabled' when it is not and opens the system to Spectre v2 attacks. The highest threat from this vulnerability is to...

kernel: Indirect Branch Prediction Barrier is force-disabled when STIBP is unavailable or enhanced IBRS is available.

A flaw was found in the Linux kernel’s implementation of the Enhanced IBPB Indirect Branch Prediction Barrier. The IBPB mitigation will be disabled when STIBP is not available or when the Enhanced Indirect Branch Restricted Speculation IBRS is available. This flaw allows a local attacker to perfo...

kernel: Indirect Branch Prediction Barrier is force-disabled when STIBP is unavailable or enhanced IBRS is available.

A flaw was found in the Linux kernel’s implementation of the Enhanced IBPB Indirect Branch Prediction Barrier. The IBPB mitigation will be disabled when STIBP is not available or when the Enhanced Indirect Branch Restricted Speculation IBRS is available. This flaw allows a local attacker to perfo...

kernel: Indirect branch speculation can be enabled after it was force-disabled by the PR_SPEC_FORCE_DISABLE prctl command.

A flaw was found in the prctl function, where it can be used to enable indirect branch speculation after it has been disabled. This call incorrectly reports it as being 'force disabled' when it is not and opens the system to Spectre v2 attacks. The highest threat from this vulnerability is to...

kernel: Indirect Branch Prediction Barrier is force-disabled when STIBP is unavailable or enhanced IBRS is available.

A flaw was found in the Linux kernel’s implementation of the Enhanced IBPB Indirect Branch Prediction Barrier. The IBPB mitigation will be disabled when STIBP is not available or when the Enhanced Indirect Branch Restricted Speculation IBRS is available. This flaw allows a local attacker to perfo...