Local denial of service via failed fault copy
Published Jul 25, 2026 · Updated Jul 25, 2026
Denial of service in Linux Kernel allows local users to hang an iommufd fault-event reader via a failed copy to userspace. In iommufd_fault_fops_read(), a copy_to_user() failure breaks only the inner list traversal, so the outer loop restores and repeatedly fetches the same fault group while retaining fault->mutex. Triggering the error requires local low-privileged access to the iommufd fault-event read path; the affected reader spins at 100% CPU and blocks other users of the held mutex.
Summary
What happened
Denial of service in Linux Kernel allows local users to hang an iommufd fault-event reader via a failed copy to userspace. In iommufd_fault_fops_read(), a copy_to_user() failure breaks only the inner list traversal, so the outer loop restores and repeatedly fetches the same fault group while retaining fault->mutex. Triggering the error requires local low-privileged access to the iommufd fault-event read path; the affected reader spins at 100% CPU and blocks other users of the held mutex.
The record
- CVE
- CVE-2026-64290
- Published
- Jul 25, 2026
- Updated
- Jul 25, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-835, T1499.004
- Attack vector
- local
- Privileges
- authenticated
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=07838f7fd529c8a6de44b601d4b7057e6c8d36ed <172fc8b19825a0f5884c38f2289188284e2d45ee
- Affected versionversion=07838f7fd529c8a6de44b601d4b7057e6c8d36ed <5539da127d03c1f6c2e2a49fdfbe331a0ccbdea8
- Affected versionversion=07838f7fd529c8a6de44b601d4b7057e6c8d36ed <f66c16b175509642ee7082df57c9bf3deaebae1a
- Affected versionversion=6.11
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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