In the Linux kernel, the following vulnerability has been resolved: KVM: Don't WARN if memory is dirtied without a vCPU when the VM is dying When marking a page dirty, complain about not having a running/loaded vCPU if and only if the VM is still alive, i.e. its refcount is non-zero. This will allow fixing a memory leak for x86 SEV-ES guests without hitting what is effectively a false positive on the WARN. For some SEV-ES VM-Exits, KVM keeps a writable mapping of a guest page across an exit to userspace, and typically unmaps the page on the next KVM_RUN. But if userspace never calls KVM_RUN after such an exit, then KVM needs to unmap the page when the vCPU is destroyed, which in turn triggers the WARN about not having a running vCPU. Alternatively, SEV-ES could temporarily load the vCPU to suppress the WARN, as is done in nested_vmx_free_vcpu() (but for completely unrelated reasons; suppressing WARN from nested_put_vmcs12_pages() is pure happenstance). But loading a vCPU during destruction is gross (ideally nVMX code would be cleaned up), risks complicating the SEV-ES code (KVM would need to ensure the temporarily load()+put() only runs when the vCPU isn't already loaded), and is ultimately pointless. The motivation for the WARN is to guard against KVM dirtying guest memory without pushing the corresponding GFN to the active vCPU's dirty ring, e.g. to ensure userspace doesn't miss a dirty page. But for the VM's refcount to reach zero, there can't be _any_ userspace mappings to the dirty ring, as mapping the dirty ring requires doing mmap() on the vCPU FD. I.e. if userspace had a valid mapping for the dirty ring, then the vCPU file and thus the owning VM would still be alive. And so since userspace can't possibly reach the dirty ring, whether or not KVM technically "misses" a push to the dirty ring is irrelevant.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - KVM: Don't WARN if memory is dirtied without a vCPU when the VM is dying When marking a page dirty,     complain about not having a running/loaded vCPU if and only if the VM is still alive, i.e. its refcount is     non-zero. This will allow fixing a memory leak for x86 SEV-ES guests without hitting what is effectively a     false positive on the WARN. For some SEV-ES VM-Exits, KVM keeps a writable mapping of a guest page across     an exit to userspace, and typically unmaps the page on the next KVM_RUN. But if userspace never calls     KVM_RUN after such an exit, then KVM needs to unmap the page when the vCPU is destroyed, which in turn     triggers the WARN about not having a running vCPU. Alternatively, SEV-ES could temporarily load the vCPU     to suppress the WARN, as is done in nested_vmx_free_vcpu() (but for completely unrelated reasons;
    suppressing WARN from nested_put_vmcs12_pages() is pure happenstance). But loading a vCPU during     destruction is gross (ideally nVMX code would be cleaned up), risks complicating the SEV-ES code (KVM     would need to ensure the temporarily load()+put() only runs when the vCPU isn't already loaded), and is     ultimately pointless. The motivation for the WARN is to guard against KVM dirtying guest memory without     pushing the corresponding GFN to the active vCPU's dirty ring, e.g. to ensure userspace doesn't miss a     dirty page. But for the VM's refcount to reach zero, there can't be _any_ userspace mappings to the dirty     ring, as mapping the dirty ring requires doing mmap() on the vCPU FD. I.e. if userspace had a valid     mapping for the dirty ring, then the vCPU file and thus the owning VM would still be alive. And so since     userspace can't possibly reach the dirty ring, whether or not KVM technically misses a push to the dirty     ring is irrelevant. (CVE-2026-53345)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
335080	openSUSE 16: cluster-md-kmp-64kb / cluster-md-kmp-azure / cluster-md-kmp-default / etc (openSUSE-SU-2026:21555-1)	Nessus	SuSE Local Security Checks	Local	high
328493	Amazon Linux 2023 : bpftool6.12, kernel6.12, kernel6.12-devel (ALAS2023-2026-1968)	Nessus	Amazon Linux Local Security Checks	Local	high
327383	Amazon Linux 2023 : bpftool6.18, kernel6.18, kernel6.18-devel (ALAS2023-2026-1925)	Nessus	Amazon Linux Local Security Checks	Local	high
324681	Linux Distros Unpatched Vulnerability : CVE-2026-53345	Nessus	Misc.	Local	medium

Detections

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CVE-2026-53345

medium

Tenable Plugins

high

high

high

medium