CVE-2026-43274

Kernel memory corruption via oversized hart IDs

Published May 6, 2026 · Updated May 6, 2026

Out-of-bounds access in affected Linux Kernel releases corrupts kernel memory on systems with oversized or noncontiguous hart IDs. The probe path and interrupt handler index the online-CPU-sized cluster_cfg array with hart IDs while writing IRQ and buffer fields or reading IRQ entries. Exposure requires the Microchip IPC SBI mailbox driver and a hart ID outside the array's CPU-index range.

CVSS severity8.4
High
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds access in affected Linux Kernel releases corrupts kernel memory on systems with oversized or noncontiguous hart IDs. The probe path and interrupt handler index the online-CPU-sized cluster_cfg array with hart IDs while writing IRQ and buffer fields or reading IRQ entries. Exposure requires the Microchip IPC SBI mailbox driver and a hart ID outside the array's CPU-index range.

The record

CVE
CVE-2026-43274
Published
May 6, 2026
Updated
May 6, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
Unavailable
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 6, 2026CVE publishedPublication date reported by the CVE source.
  2. May 6, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <0442b6229e2eedc95a6d3d18ce75dec7f5b5377c
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <95438699c92947155823dcd3918049a07f3cd867
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <f7c330a8c83c9b0332fd524097eaf3e69148164d

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <0442b6229e2eedc95a6d3d18ce75dec7f5b5377c; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <95438699c92947155823dcd3918049a07f3cd867; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <f7c330a8c83c9b0332fd524097eaf3e69148164d

Published CVSS scores

8.4UbuntuCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
Privilegesunauthenticated
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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