CVE-2026-64428

Service interruption via sleepable IRQ spinlock

Published Jul 25, 2026 · Updated Jul 25, 2026

Improper locking in the SCH GPIO IRQ path in affected Linux Kernel releases allows attackers to interrupt service during IRQ startup. During the non-sleepable path, sch_irq_unmask() reaches sch_irq_mask_unmask(), which acquires a regular spinlock that becomes sleepable under PREEMPT_RT. Triggering requires a PREEMPT_RT kernel and the SCH GPIO IRQ path; published sources do not establish an unprivileged user-space route.

CVSS severityUnavailable
Unscored
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

Improper locking in the SCH GPIO IRQ path in affected Linux Kernel releases allows attackers to interrupt service during IRQ startup. During the non-sleepable path, sch_irq_unmask() reaches sch_irq_mask_unmask(), which acquires a regular spinlock that becomes sleepable under PREEMPT_RT. Triggering requires a PREEMPT_RT kernel and the SCH GPIO IRQ path; published sources do not establish an unprivileged user-space route.

The record

CVE
CVE-2026-64428
Published
Jul 25, 2026
Updated
Jul 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499.004
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Jul 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 25, 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=5.13
  2. Affected versionversion=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <286533cb14a3c8a8bd39ff64ea2fc8e1aa0f638b
  3. Affected versionversion=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <3b1aa05ec27eeccc889ecaa3f2d9baa9f453e50d
  4. Affected versionversion=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <41cad91a09d69e8fff4e936db29b1054b4e9f9f7
  5. Affected versionversion=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <4508366ab7dd0c2917a51a9c2e23cc1b9d35157a
  6. Affected versionversion=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <4f03a15cc73c83740fc355ee22b336492d17b4da
  7. Affected versionversion=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <7a550256d68bbdfa0903ab1c4595c04a6815493a
  8. Affected versionversion=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <a235cec779bb39ec8f961a935b28a2ce278c6c64

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linux Kernelversion=5.13; version=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <286533cb14a3c8a8bd39ff64ea2fc8e1aa0f638b; version=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <3b1aa05ec27eeccc889ecaa3f2d9baa9f453e50d; version=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <41cad91a09d69e8fff4e936db29b1054b4e9f9f7; version=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <4508366ab7dd0c2917a51a9c2e23cc1b9d35157a; version=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <4f03a15cc73c83740fc355ee22b336492d17b4da; version=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <7a550256d68bbdfa0903ab1c4595c04a6815493a; version=7a81638485c1a62a87b4c391ecc9c651a4a9dc19 <a235cec779bb39ec8f961a935b28a2ce278c6c64

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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No observations available

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

Weakness, pattern, technique

T1499.004Endpoint Denial of Service: Application or System Exploitation

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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