Kernel code execution via iommufd refcount race
Published Dec 9, 2025 · Updated Aug 5, 2026
Use-after-free in Linux kernel iommufd 6.2 through 6.4.7 allows local users to read and write kernel memory via an ioctl race. IOMMUFD_DESTROY raises an object refcount without holding destroy_rwsem, so a concurrent device close leaves a stale iommufd_access that dereferences freed kernel heap. Local access to /dev/iommu or /dev/vfio/vfio is required; exploitation enables control-flow hijacking or a kernel crash.
Summary
What happened
Use-after-free in Linux kernel iommufd 6.2 through 6.4.7 allows local users to read and write kernel memory via an ioctl race. IOMMUFD_DESTROY raises an object refcount without holding destroy_rwsem, so a concurrent device close leaves a stale iommufd_access that dereferences freed kernel heap. Local access to /dev/iommu or /dev/vfio/vfio is required; exploitation enables control-flow hijacking or a kernel crash.
The record
- CVE
- CVE-2023-53795
- Published
- Dec 9, 2025
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1068
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Dec 9, 2025CVE publishedPublication date reported by the CVE source.
- Aug 5, 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?
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- Affected versionversion=2ff4bed7fee72ba1abfcff5f11ae8f8e570353f2 <495b327435b0298e9b3b434f5834d459a93673ce
- Affected versionversion=2ff4bed7fee72ba1abfcff5f11ae8f8e570353f2 <99f98a7c0d6985d5507c8130a981972e4b7b3bdc
- Affected versionversion=6.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Technologies
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Your stack
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