Protected-memory writes via stale IOMMU translations
Published Nov 16, 2021 · Updated Sep 16, 2024
Improper initialization in AMD EPYC, Ryzen, and Athlon processors allows local users to corrupt protected memory through an I/O device. The IOMMU fails to flush a Translation Lookaside Buffer, leaving a stale translation that lets the device write outside its authorized memory range. Exploitation requires local low-privileged access and control of a DMA-capable I/O device; the documented consequence is loss of memory integrity.
Summary
What happened
Improper initialization in AMD EPYC, Ryzen, and Athlon processors allows local users to corrupt protected memory through an I/O device. The IOMMU fails to flush a Translation Lookaside Buffer, leaving a stale translation that lets the device write outside its authorized memory range. Exploitation requires local low-privileged access and control of a DMA-capable I/O device; the documented consequence is loss of memory integrity.
The record
- CVE
- CVE-2021-26312
- Published
- Nov 16, 2021
- Updated
- Sep 16, 2024
- Vendor
- AMD
- Product
- AMD EPYC Processors
- Classifications
- CWE-668, CWE-665
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Nov 16, 2021CVE publishedPublication date reported by the CVE source.
- Sep 16, 2024Record updatedLatest update available in the CVE record.
Exploitability
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- Affected versionversion=various
What conditions does exploitation require?
What is affected?
Attacks
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Weakness, pattern, technique
Public exploit references
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