VulnerabilityPublished 18 Oct 2026

CVE-2026-98718: Linux kernel · KVM: SEV: Do cache maintenance on the source VM before clearing SEV state

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in de83ff6a4d8f3618473bedb3c4400020c22e8a8a : patch Linux kernel soon.

Data as of 26 Oct 2026, 12:55 UTC

Severity

High

Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD

EPSS: 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in de83ff6a4d8f3618473bedb3c4400020c22e8a8a, 973ea70393e885e540f714904e51bc6cac80e3d7, 8b7d4f68fef96cebe0b6dbb6e5607772337f7369 +2

Exploitation evidence

Disclosed: evidence found.
CVE published 18 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade Linux to de83ff6a4d8f3618473bedb3c4400020c22e8a8a, 973ea70393e885e540f714904e51bc6cac80e3d7 or 8b7d4f68fef96cebe0b6dbb6e5607772337f7369; Linux and linux/kernel to 7.2.10 or 6.18.56.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ d4cc2dff12116a700add601c0262132cc26e1b2c, < de83ff6a4d8f3618473bedb3c4400020c22e8a8a	Fixed in de83ff6a4d8f3618473bedb3c4400020c22e8a8a
LinuxLinux	Affected ≥ 93de2a6a4b91b72607136dd656edf03fb399d27f, < 973ea70393e885e540f714904e51bc6cac80e3d7	Fixed in 973ea70393e885e540f714904e51bc6cac80e3d7
LinuxLinux	Affected ≥ 37dfb676fafd1eef36fe0bb649607afbb0d5521b, < 8b7d4f68fef96cebe0b6dbb6e5607772337f7369	Fixed in 8b7d4f68fef96cebe0b6dbb6e5607772337f7369
LinuxLinux	Affected >=7.2.9 <7.2.10	Fixed in 7.2.10
LinuxLinux	Affected >=6.18.55 <6.18.56	Fixed in 6.18.56
Linuxlinux/kernel`pkg:deb/linux/kernel`Other threats	Affected >=6.18.55 <6.18.56 >=7.2.9 <7.2.10	Fixed in 6.18.56 7.2.10

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Fixed versions are available in Linux kernel releases 6.18.56 and 7.2.10 and corresponding commits. Users should upgrade to these or later versions to remediate the issue. No additional mitigation steps are required beyond applying the official kernel updates.

Description

A vulnerability in the Linux kernel's KVM SEV implementation involves improper cache maintenance timing during intra-host VM migration. The issue arises because cache flushes are performed after clearing the SEV active state on the source VM, creating a small window where memory pages could be reclaimed and reused without proper cache flushing. This could lead to memory corruption or data leakage between virtual machines.

Impact

The vulnerability could allow a race condition during VM migration that leads to memory pages being reclaimed and reused without proper cache flushing. This may result in memory corruption or leakage of encrypted guest data, undermining the isolation guarantees of SEV. However, no known exploits in the wild have been reported.

Summary

CVE-2026-98718 addresses a flaw in the Linux kernel's KVM SEV (Secure Encrypted Virtualization) feature where cache maintenance was done after clearing the SEV active state on the source VM during intra-host migration. The vulnerability occurs because clearing the SEV active flag before flushing caches allows a race condition where memory reclaim can skip cache flushes, potentially causing the host to reuse memory pages containing stale encrypted data. The fix explicitly performs cache maintenance before clearing the SEV active state to prevent this race condition and ensure memory integrity.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 09:59 UTC

Technical details

References

Community reviews

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