Kernel scheduling failure via mutex-taking IRQ lookup
Published Jul 25, 2026 · Updated Jul 25, 2026
Concurrency flaw in the Linux kernel causes an atomic-context scheduling failure during NTB EPF interrupt handling on affected systems. The ntb_epf_vec_isr() hardirq handler calls pci_irq_vector(); its msi_get_virq() path takes a mutex and attempts to sleep while atomic. Exposure requires the ntb_hw_epf driver and delivery of its vector interrupt; the CNA reports a scheduling-while-atomic diagnostic but does not establish a remote vector or host hang.
Summary
What happened
Concurrency flaw in the Linux kernel causes an atomic-context scheduling failure during NTB EPF interrupt handling on affected systems. The ntb_epf_vec_isr() hardirq handler calls pci_irq_vector(); its msi_get_virq() path takes a mutex and attempts to sleep while atomic. Exposure requires the ntb_hw_epf driver and delivery of its vector interrupt; the CNA reports a scheduling-while-atomic diagnostic but does not establish a remote vector or host hang.
The record
- CVE
- CVE-2026-64430
- Published
- Jul 25, 2026
- Updated
- Jul 25, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- Unavailable
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Jul 25, 2026CVE publishedPublication date reported by the CVE source.
- 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.
- Affected versionversion=5.12
- Affected versionversion=812ce2f8d14ea791edd88c36ebcc9017bf4c88cb <174a97f21bf9c54fa37ec0f321692e862ea130a3
- Affected versionversion=812ce2f8d14ea791edd88c36ebcc9017bf4c88cb <1dba8444ac0100133d72374634f6d7451fff1ccc
- Affected versionversion=812ce2f8d14ea791edd88c36ebcc9017bf4c88cb <33bba331a4a5fee8b6026fe72eca13cceeec1b7b
- Affected versionversion=812ce2f8d14ea791edd88c36ebcc9017bf4c88cb <4dcddc1c794d1c65eda68f1f8dd04a0fecc0870f
- Affected versionversion=812ce2f8d14ea791edd88c36ebcc9017bf4c88cb <6350df503897d57c5634f71b0767d48c3b837583
- Affected versionversion=812ce2f8d14ea791edd88c36ebcc9017bf4c88cb <aff271b12a1eb8c8b3da19223ae1a6abe1e8168b
- Affected versionversion=812ce2f8d14ea791edd88c36ebcc9017bf4c88cb <f71e8d9875069fa73e335f63f02ec6e52e3aaa51
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
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Public exploit references
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Technologies
Your stack
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Your stack
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