CVE-2026-23443

Local system crash via stale ACPI device pointers

Published Apr 3, 2026 · Updated Apr 3, 2026

Use-after-free in the Linux kernel ACPI processor driver allows local users to crash the system through PIIX4 errata handling. The acpi_processor_errata_piix4 function drops references to PIIX4 device objects and then debug logging dereferences the stale device pointers. Low-privileged local access is required, and the documented consequence is a kernel crash without reported data disclosure or modification.

CVSS severity5.5
Medium
EPSS probability0.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in the Linux kernel ACPI processor driver allows local users to crash the system through PIIX4 errata handling. The acpi_processor_errata_piix4 function drops references to PIIX4 device objects and then debug logging dereferences the stale device pointers. Low-privileged local access is required, and the documented consequence is a kernel crash without reported data disclosure or modification.

The record

CVE
CVE-2026-23443
Published
Apr 3, 2026
Updated
Apr 3, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-476, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 3, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 3, 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=01e8751b37a366b1ca561add0042f2ceb18c03bf <edf4c2aaee08e8fd503fbae705c801e92a0b55d7
  2. Affected versionversion=0398b641be2b66c2fc7e0163c606ef19372e7ad5 <8583f62259e1b315d5239371adfb36939cdab741
  3. Affected versionversion=06724a60cfa9767ea90b0f5d3dfb5cdd251b64f5
  4. Affected versionversion=29f60d3d06818d40118a30d663231f027ae87a05 <98473309a36acc271009b85e0bb53a4c0dddf5c2
  5. Affected versionversion=7.0-rc1
  6. Affected versionversion=ad86ac604f8391c0212a91412d4f764c7a85f254 <2e369ba9eb7b8a06e9cc35a3e7fe73e59272f8c2
  7. Affected versionversion=b803811485ac0b2f774b6bf3abc8b999ba3b7033 <e0c470049344e9346fff79d7e2362212c216665e
  8. Affected versionversion=f132e089fe89cadc2098991f0a3cb05c3f824ac6 <bf504b229cb8d534eccbaeaa23eba34c05131e25

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=01e8751b37a366b1ca561add0042f2ceb18c03bf <edf4c2aaee08e8fd503fbae705c801e92a0b55d7; version=0398b641be2b66c2fc7e0163c606ef19372e7ad5 <8583f62259e1b315d5239371adfb36939cdab741; version=06724a60cfa9767ea90b0f5d3dfb5cdd251b64f5; version=29f60d3d06818d40118a30d663231f027ae87a05 <98473309a36acc271009b85e0bb53a4c0dddf5c2; version=7.0-rc1; version=ad86ac604f8391c0212a91412d4f764c7a85f254 <2e369ba9eb7b8a06e9cc35a3e7fe73e59272f8c2; version=b803811485ac0b2f774b6bf3abc8b999ba3b7033 <e0c470049344e9346fff79d7e2362212c216665e; version=f132e089fe89cadc2098991f0a3cb05c3f824ac6 <bf504b229cb8d534eccbaeaa23eba34c05131e25

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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

CWE-476NULL Pointer Dereference
T1499.004Application or System Exploitation

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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