CVE-2026-98471

HIGH
MEDIUM Priority: 0.01 BB Relevance: 39/100
Published: 2026-10-18 Modified: 2026-10-24 First seen: 2026-10-29 Status: active

Attack Surface

Low Complexity No Interaction Integ. Impact

CVSS Vector Breakdown

AV: Local
AC: Low
PR: Low
UI: None
S: Unchanged
C: None
I: High
A: High

Description

In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Do cache maintenance on the source VM during intra-host migration Manually perform cache maintenance on the source VM during intra-host migration to ensure no stale data is left in CPU caches after the VM is destroyed. Because the source VM is "converted" to a non-SEV VM, KVM's memory reclaim flows won't trigger cache maintenance, e.g. when all guest memory is reclaimed in response to detaching from the mmu_notifier. Note, relying on the destination VM to do cache maintenance isn't an option as KVM doesn't require identical guest memory configurations, i.e. the source VM may have access to memory that the destination VM does not. Enforcing equivalent memory configurations is infeasible, as it would require a *deep* comparison of memslots, e.g. to verify that not only are the memslot identical, but what the memslots point at is also identical.

Bug Bounty Relevance

39 / 100
✓ Low complexity
✓ No user interaction

CVSS Score

7.1 / 10.0 v3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

EPSS — Exploitation Probability

0.16%
Raw Score 0.001580
Percentile 5.0%
Date 2026-11-03

EPSS Trend

2026-11-03
0.00158
2026-11-02
0.00158
2026-11-01
0.00158
2026-10-31
0.00158
2026-10-30
0.00158
2026-10-29
0.00158
2026-10-28
0.00158

Intelligence Sources

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