Data exposure or service interruption via SPI race
Published Nov 14, 2023 · Updated Aug 2, 2024
A TOCTOU race in the ASP Bootloader on affected AMD processors allows physically proximate attackers to expose data or interrupt service. After verifying an SPI ROM record in memory, the bootloader later consumes mutable ROM content without ensuring that it still matches the checked content. Physical access is required to alter the record in that interval, enabling confidentiality loss or a boot-time denial of service.
Summary
What happened
A TOCTOU race in the ASP Bootloader on affected AMD processors allows physically proximate attackers to expose data or interrupt service. After verifying an SPI ROM record in memory, the bootloader later consumes mutable ROM content without ensuring that it still matches the checked content. Physical access is required to alter the record in that interval, enabling confidentiality loss or a boot-time denial of service.
The record
- CVE
- CVE-2023-20521
- Published
- Nov 14, 2023
- Updated
- Aug 2, 2024
- Vendor
- AMD
- Product
- Athlon 3000 Series Mobile Processors with Radeon Graphics (Pollock)
- Classifications
- CWE-367, T1495
- Attack vector
- physical
- Privileges
- Unavailable
Timeline
How it unfolded
- Nov 14, 2023CVE publishedPublication date reported by the CVE source.
- Aug 2, 2024Record 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=various
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What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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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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