Important: Red Hat Security Advisory: kernel security update

An update for kernel is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System CVSS base score, which gives a detailed severity rating, is available for each vulnerability from th...

KVM: SEV: Reject attempts to sync VMSA of an already-launched/encrypted vCPU

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SUSE CVE-2026-31588

In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Use scratch field in MMIO fragment to hold small write values When exiting to userspace to service an emulated MMIO write, copy the to-be-written value to a scratch field in the MMIO fragment if the size of the data...

Linux Distros Unpatched Vulnerability : CVE-2026-31558

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - In the Linux kernel, the following vulnerability has been resolved: LoongArch: KVM: Make kvmgetvcpubycpuid more robust kvmgetvcpubycpuid takes a cpuid parameter...

CVE-2026-31592

A flaw was found in the Linux kernel's KVM Kernel-based Virtual Machine subsystem. A local user could exploit a concurrency issue by failing to properly protect the sevmemencregisterregion function with the kvm-lock. This can lead to an unstable state if KVM initialization fails, resulting in a...

CVE-2026-31569

A flaw was found in the Linux kernel's Kernel-based Virtual Machine KVM component. When a specific internal data structure, known as EIOINTC's coremap, is empty, the system incorrectly processes a processor ID. This error can lead to an out-of-bounds memory access, meaning the system tries to rea...

CVE-2026-31591

In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish Lock all vCPUs when synchronizing and encrypting VMSAs for SNP guests, as allowing userspace to manipulate and/or run a vCPU while its state is being...

DEBIAN-CVE-2026-31590

In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Drop WARN on large size for KVMMEMORYENCRYPTREGREGION Drop the WARN in sevpinmemory on npages overflowing an int, as the WARN is comically trivially to trigger from userspace, e.g. by doing: struct kvmencregion range =...

CVE-2026-31588

In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Use scratch field in MMIO fragment to hold small write values When exiting to userspace to service an emulated MMIO write, copy the to-be-written value to a scratch field in the MMIO fragment if the size of the data...

DEBIAN-CVE-2026-31553

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Fix the descriptor address in kvmatswapdesc Using "u64 user hva + offset" to get the virtual addresses of S1/S2 descriptors looks really wrong, if offset is not zero. What we want to get for swapping is hva + offset,...

CVE-2026-31564

In the Linux kernel, the following vulnerability has been resolved: LoongArch: KVM: Fix base address calculation in kvmeiointcregsaccess In function kvmeiointcregsaccess, the register base address is caculated from array base address plus offset, the offset is absolute value from the base address...

CVE-2026-31558

In the Linux kernel, the following vulnerability has been resolved: LoongArch: KVM: Make kvmgetvcpubycpuid more robust kvmgetvcpubycpuid takes a cpuid parameter whose type is int, so cpuid can be negative. Let kvmgetvcpubycpuid return NULL for this case so as to make it more robust. This fix an...

EUVD-2026-25484

In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish Lock all vCPUs when synchronizing and encrypting VMSAs for SNP guests, as allowing userspace to manipulate and/or run a vCPU while its state is being...

CVE-2026-31592

CVE-2026-31592 affects the Linux kernel KVM subsystem. The vulnerability arises when sev_mem_enc_register_region() is not protected by kvm->lock before sev_guest() is checked, risking state corruption if KVM_INIT{2} fails and an uninitialized sev->regions_list is touched, potentially causin...

EUVD-2026-25485

In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Protect all of sevmemencregisterregion with kvm-lock Take and hold kvm-lock for before checking sevguest in sevmemencregisterregion, as sevguest isn't stable unless kvm-lock is held or KVM can guarantee KVMSEVINIT2 has...

CVE-2026-31591 KVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish

In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Lock all vCPUs when synchronzing VMSAs for SNP launch finish Lock all vCPUs when synchronizing and encrypting VMSAs for SNP guests, as allowing userspace to manipulate and/or run a vCPU while its state is being...

CVE-2026-31588

In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Use scratch field in MMIO fragment to hold small write values When exiting to userspace to service an emulated MMIO write, copy the to-be-written value to a scratch field in the MMIO fragment if the size of the data...

CVE-2026-31588 KVM: x86: Use scratch field in MMIO fragment to hold small write values

In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Use scratch field in MMIO fragment to hold small write values When exiting to userspace to service an emulated MMIO write, copy the to-be-written value to a scratch field in the MMIO fragment if the size of the data...

CVE-2026-31569

In the Linux kernel, the following vulnerability has been resolved: LoongArch: KVM: Handle the case that EIOINTC's coremap is empty EIOINTC's coremap in eiointcupdateswcoremap can be empty, currently we get a cpuid with -1 in this case, but we actually need 0 because it's similar as the case that...

CVE-2026-31569 LoongArch: KVM: Handle the case that EIOINTC's coremap is empty

In the Linux kernel, the following vulnerability has been resolved: LoongArch: KVM: Handle the case that EIOINTC's coremap is empty EIOINTC's coremap in eiointcupdateswcoremap can be empty, currently we get a cpuid with -1 in this case, but we actually need 0 because it's similar as the case that...