CVE-2026-43171

Kernel memory disclosure or OOPS via CPER underflow

Published May 6, 2026 · Updated May 6, 2026

Integer underflow in Linux Kernel CPER parsing allows local users to disclose kernel memory or trigger an OOPS through malformed firmware records. cper_print_fw_err() subtracts an unchecked section offset from the record length, so an offset beyond the record wraps the length and drives an oversized hex dump. Reachability requires a malformed firmware error record; processing can spend substantial time dumping memory, disclose kernel data, or access an unmapped region and raise an OOPS.

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

Integer underflow in Linux Kernel CPER parsing allows local users to disclose kernel memory or trigger an OOPS through malformed firmware records. cper_print_fw_err() subtracts an unchecked section offset from the record length, so an offset beyond the record wraps the length and drives an oversized hex dump. Reachability requires a malformed firmware error record; processing can spend substantial time dumping memory, disclose kernel data, or access an unmapped region and raise an OOPS.

The record

CVE
CVE-2026-43171
Published
May 6, 2026
Updated
May 6, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-191, T1499
Attack vector
local
Privileges
authenticated

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

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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=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <02de64ab54b4bb0f1b21bb324aeff3b08612be33
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <0e09b522f2622841389c3b2f9ac4969e35c0809d
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <54e131db4cdffd946db890ff33ff2647053fd4f6
  4. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <55cc6fe5716f678f06bcb95140882dfa684464ec
  5. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5a9b1dda8481b82851a655c3bcc5b44879b95334
  6. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <64ae5aaa7ac93c83da456039e8ec747bfa8a7cff
  7. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <7780c0bad2a3a70a8c0113a33c02f4151d901eb3
  8. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a8419f5f2c5f2d80848ddabb2b95cf0da84a5f91

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <02de64ab54b4bb0f1b21bb324aeff3b08612be33; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <0e09b522f2622841389c3b2f9ac4969e35c0809d; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <54e131db4cdffd946db890ff33ff2647053fd4f6; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <55cc6fe5716f678f06bcb95140882dfa684464ec; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5a9b1dda8481b82851a655c3bcc5b44879b95334; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <64ae5aaa7ac93c83da456039e8ec747bfa8a7cff; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <7780c0bad2a3a70a8c0113a33c02f4151d901eb3; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a8419f5f2c5f2d80848ddabb2b95cf0da84a5f91

Published CVSS scores

5.5Oracle LinuxCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
7.0Amazon LinuxCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5SUSECVSS: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

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

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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-191Integer Underflow (Wrap or Wraparound)
T1499Endpoint Denial of Service

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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