CVE-2026-89929

Stale nested-guest mappings via cross-CPU INVVPID

Published Sep 16, 2026 · Updated Sep 16, 2026

A TLB invalidation flaw in Linux KVM before 6.12.110, 6.18.51, and 7.2.5 allows guest OS users to retain stale nested-guest mappings. KVM emulates an L1 INVVPID with vpid02 on the current physical CPU rather than the CPU where L2 last ran, so that CPU's TLB entries remain unflushed. Reachability requires Intel VMX nested virtualization, an L2 exit, L1 migration across physical CPUs, INVVPID execution, and migration back; the published record specifies no consequence beyond stale translations.

CVSS severityUnavailable
Unscored
EPSS probabilityUnavailable
No score available in this record
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

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Summary

What happened

A TLB invalidation flaw in Linux KVM before 6.12.110, 6.18.51, and 7.2.5 allows guest OS users to retain stale nested-guest mappings. KVM emulates an L1 INVVPID with vpid02 on the current physical CPU rather than the CPU where L2 last ran, so that CPU's TLB entries remain unflushed. Reachability requires Intel VMX nested virtualization, an L2 exit, L1 migration across physical CPUs, INVVPID execution, and migration back; the published record specifies no consequence beyond stale translations.

The record

CVE
CVE-2026-89929
Published
Sep 16, 2026
Updated
Sep 16, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 16, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <6.12.110
  2. Affected versionversion=0 <6.18.51
  3. Affected versionversion=0 <7.2.5
  4. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <27bdeb5fd19046ffba9ff234e92fe553eb2efb30
  5. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <6d00e67326d831e6e610933a3800712f4ffe6ec1
  6. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <9941850e8adf164d005dbd3774c4b79e91a3cb8e
  7. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d03e721801ac54b9fdf05668aa0c069f07913b68

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=0 <6.12.110; version=0 <6.18.51; version=0 <7.2.5; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <27bdeb5fd19046ffba9ff234e92fe553eb2efb30; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <6d00e67326d831e6e610933a3800712f4ffe6ec1; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <9941850e8adf164d005dbd3774c4b79e91a3cb8e; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d03e721801ac54b9fdf05668aa0c069f07913b68

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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