CVE-2026-89930Public exploit

Stale L2 translations via missed TLB flush

Published Sep 16, 2026 · Updated Sep 16, 2026

Improper TLB invalidation in Linux KVM allows guest OS users to retain stale L2 translations after a failed nested VM entry. The nVMX transition path updates last_vpid when L1 changes L2's VPID, but a failed entry does not service the queued local TLB flush, so a later successful entry can reuse cached translations. The issue requires Intel nested VMX with VPID-related flush state, and upstream material does not state whether stale translations permit disclosure, modification, or interruption.

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

Improper TLB invalidation in Linux KVM allows guest OS users to retain stale L2 translations after a failed nested VM entry. The nVMX transition path updates last_vpid when L1 changes L2's VPID, but a failed entry does not service the queued local TLB flush, so a later successful entry can reuse cached translations. The issue requires Intel nested VMX with VPID-related flush state, and upstream material does not state whether stale translations permit disclosure, modification, or interruption.

The record

CVE
CVE-2026-89930
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=4.4
  2. Affected versionversion=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <05a0b701d1089fb57beeb8982f23c3bbafe0fa8b
  3. Affected versionversion=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <1025b938dc439b75c720a568a855a13eeb245686
  4. Affected versionversion=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <312cdb6d8940827dea63a7a52fb714a5049f06d1
  5. Affected versionversion=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <62c3ee4c9f0e2efef5157358b3549e50ede96d73
  6. Affected versionversion=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <c0c66cd575e31218da6a7d104c6ef80b0830b60c
  7. Affected versionversion=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <c43563e7518e65ec6ccaa6a65f84c5af5ca5d379
  8. Affected versionversion=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <f74fccdf4f7fb0780cd84944108d35f3d9dc46a7

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=4.4; version=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <05a0b701d1089fb57beeb8982f23c3bbafe0fa8b; version=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <1025b938dc439b75c720a568a855a13eeb245686; version=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <312cdb6d8940827dea63a7a52fb714a5049f06d1; version=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <62c3ee4c9f0e2efef5157358b3549e50ede96d73; version=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <c0c66cd575e31218da6a7d104c6ef80b0830b60c; version=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <c43563e7518e65ec6ccaa6a65f84c5af5ca5d379; version=5c614b3583e7b6dab0c86356fa36c2bcbb8322a0 <f74fccdf4f7fb0780cd84944108d35f3d9dc46a7

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 exploitPublished

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

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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