Memory corruption and service interruption via ASP TOCTOU
Published Jan 10, 2023 · Updated Apr 7, 2025
TOCTOU in the AMD Secure Processor on second- and third-generation EPYC processors allows physically proximate attackers to corrupt memory. The ASP uses a buffer after its checked bounds can change, permitting an out-of-bounds write during the race window. Physical access and successful race timing are required; exploitation can compromise firmware-managed state or interrupt service.
Summary
What happened
TOCTOU in the AMD Secure Processor on second- and third-generation EPYC processors allows physically proximate attackers to corrupt memory. The ASP uses a buffer after its checked bounds can change, permitting an out-of-bounds write during the race window. Physical access and successful race timing are required; exploitation can compromise firmware-managed state or interrupt service.
The record
- CVE
- CVE-2023-20523
- Published
- Jan 10, 2023
- Updated
- Apr 7, 2025
- Vendor
- AMD
- Product
- AMD EPYC 7002 Series Processors
- Classifications
- CWE-367
- Attack vector
- physical
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 10, 2023CVE publishedPublication date reported by the CVE source.
- Apr 7, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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- Affected versionversion=various
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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
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Your stack
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