CVE-2026-98718
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.
Affected versions
Linux kernel versions
6.18.55,
7.2.9
and later are affected. Fixed in
6.18.56,
7.2.10
and their respective stable series.
References
3 totalFrequently asked questions
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What is CVE-2026-98718?
CVE-2026-98718 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 6.18.55 onward and has been patched in 6.18.56 and 7.2.10. CVE-2026-98718 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-98718?
Yes. CVE-2026-98718 has been patched. Fixed versions include 6.18.56 and 7.2.10. If you are running Linux kernel 6.18.55 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-98718 actively exploited?
No. CVE-2026-98718 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.