Live › vulnerability › CVE-2026-98718
Go to dashboardIn the Linux kernel's KVM SEV code, the source VM's caches were flushed after its SEV active state was cleared during intra-host migration, leaving a race window. A reclaimed page could receive stale encrypted guest data written over the new owner's contents.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 21:57 UTC. All times on this page are UTC.
Hosts running Linux KVM with AMD SEV or SEV-ES guests that perform intra-host migration are the systems concerned. Hosts without AMD SEV guests, or without KVM, are not affected.
No product ranges from the sources yet.
Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
In the Linux kernel, the following vulnerability has been resolved:
KVM: SEV: Do cache maintenance on the source VM before clearing SEV state
Explicitly flush caches after intra-host migration before clearing "SEV active" on the source VM, as doing cache maintenance afterwards creates a tiny window where memory reclaim could return memory to the host without performing a cache flush, e.g. as pointed out by Sashiko:
CPU1 in sev_migrate_from(): src->active = false;
CPU2 running concurrent unmap: Since active is false, the automatic cache flush in sev_guest_memory_reclaimed is skipped. The host frees and reallocates the page.
CPU1 in sev_migrate_from(): sev_writeback_caches(src_kvm); Executes a hardware cache flush (wbnoinvd), which writes the guest's old dirty ciphertext over the new page owner's data.
This page as .md · .json · in your agent: get_signal("CVE-2026-98718")
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