CVE-2026-98640Public exploitHinoki check available

Kernel page fault via unchecked PCI BAR

Published Oct 18, 2026 · Updated Oct 18, 2026

Out-of-bounds MMIO access in Linux's amd_sfh driver allows attackers to cause a kernel page fault via an undersized PCI BAR. The amd_mp2_pci_probe function maps BAR 2 without validating its size, and mp2_select_ops reads AMD_P2C_MSG3 beyond that mapping. Triggering requires binding the driver to a device with an undersized BAR 2; the documented consequence is a probe-time kernel fault, not demonstrated code execution.

CVSS severityUnavailable
Unscored
EPSS probability0.21%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Out-of-bounds MMIO access in Linux's amd_sfh driver allows attackers to cause a kernel page fault via an undersized PCI BAR. The amd_mp2_pci_probe function maps BAR 2 without validating its size, and mp2_select_ops reads AMD_P2C_MSG3 beyond that mapping. Triggering requires binding the driver to a device with an undersized BAR 2; the documented consequence is a probe-time kernel fault, not demonstrated code execution.

The record

CVE
CVE-2026-98640
Published
Oct 18, 2026
Updated
Oct 18, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Oct 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 18, 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=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <5f9e2ecb725adced013fbf5f94b9f185fad2e7d9
  2. Affected versionversion=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <5ff24aa7af0bca0780fe4e6effce902065f2c0a7
  3. Affected versionversion=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <65bcc5f89704efe5b9d69d4ea2c1002d90c31382
  4. Affected versionversion=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <7b3747d77767f066ccf4a9e8e3a8381643ab5368
  5. Affected versionversion=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <92bf2883da0306ab9d1eb794acd1058fc5088ebc
  6. Affected versionversion=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <dc687489131559ee52f447592f6d039a5a013061
  7. Affected versionversion=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <ee25833f037fa22d23ffdbfeebabe3579e8a0346
  8. Affected versionversion=5.11

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <5f9e2ecb725adced013fbf5f94b9f185fad2e7d9; version=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <5ff24aa7af0bca0780fe4e6effce902065f2c0a7; version=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <65bcc5f89704efe5b9d69d4ea2c1002d90c31382; version=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <7b3747d77767f066ccf4a9e8e3a8381643ab5368; version=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <92bf2883da0306ab9d1eb794acd1058fc5088ebc; version=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <dc687489131559ee52f447592f6d039a5a013061; version=4f567b9f8141a86c7d878fadf136e5d1408e3e61 <ee25833f037fa22d23ffdbfeebabe3579e8a0346; version=5.11

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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Activity data is delayed. The latest report is Sep 28, 2026.

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No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1499.004Application or System Exploitation

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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