CVE-2026-64149

Device initialization failure via false RAM classification

Published Jul 19, 2026 · Updated Jul 19, 2026

Denial of service in Linux Kernel 6.18 allows local users to interrupt device initialization through failed ARM64 MMIO mapping. dma_map_resource() treats pfn_valid() as proof that a PFN is RAM, so MMIO sharing a SPARSEMEM section with RAM produces DMA_MAPPING_ERROR. Reachability requires ARM64 SPARSEMEM section overlap between RAM and an MMIO address; the documented Raspberry Pi 4 case prevents the SPI driver probe from completing.

CVSS severity5.5
Medium
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

Denial of service in Linux Kernel 6.18 allows local users to interrupt device initialization through failed ARM64 MMIO mapping. dma_map_resource() treats pfn_valid() as proof that a PFN is RAM, so MMIO sharing a SPARSEMEM section with RAM produces DMA_MAPPING_ERROR. Reachability requires ARM64 SPARSEMEM section overlap between RAM and an MMIO address; the documented Raspberry Pi 4 case prevents the SPI driver probe from completing.

The record

CVE
CVE-2026-64149
Published
Jul 19, 2026
Updated
Jul 19, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
Unavailable
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 19, 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=6.18
  2. Affected versionversion=f7326196a781622b33bfbdabb00f5e72b5fb5679 <004a777879ff629f6e0ca3d09ad09fa3452bcc4d
  3. Affected versionversion=f7326196a781622b33bfbdabb00f5e72b5fb5679 <181e67bc11c5ec5b87c6c512c2078752b23ca8d4
  4. Affected versionversion=f7326196a781622b33bfbdabb00f5e72b5fb5679 <af0c3f05866237f7592219bfe05387bc3bfc99b5

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=6.18; version=f7326196a781622b33bfbdabb00f5e72b5fb5679 <004a777879ff629f6e0ca3d09ad09fa3452bcc4d; version=f7326196a781622b33bfbdabb00f5e72b5fb5679 <181e67bc11c5ec5b87c6c512c2078752b23ca8d4; version=f7326196a781622b33bfbdabb00f5e72b5fb5679 <af0c3f05866237f7592219bfe05387bc3bfc99b5

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

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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