Memory disclosure and corruption via malformed SMC call
Published Dec 16, 2025 · Updated Dec 16, 2025
Buffer overflows in AmpereOne AC03, AC04, and M firmware allow local users to disclose Secure-EL0 data or corrupt mapped memory. A malformed SMC call makes the UEFI-MM Boot Error Record Table driver read or write beyond its buffer within memory mapped to the secure partition. Reaching the flaw requires high local privileges; affected releases are AC03 before 3.5.9.3, AC04 before 4.4.5.2, and M before 5.4.5.1, and corruption can hang the system or escalate privileges.
Summary
What happened
Buffer overflows in AmpereOne AC03, AC04, and M firmware allow local users to disclose Secure-EL0 data or corrupt mapped memory. A malformed SMC call makes the UEFI-MM Boot Error Record Table driver read or write beyond its buffer within memory mapped to the secure partition. Reaching the flaw requires high local privileges; affected releases are AC03 before 3.5.9.3, AC04 before 4.4.5.2, and M before 5.4.5.1, and corruption can hang the system or escalate privileges.
The record
- CVE
- CVE-2025-62862
- Published
- Dec 16, 2025
- Updated
- Dec 16, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, CWE-125, T1068
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Dec 16, 2025CVE publishedPublication date reported by the CVE source.
- Dec 16, 2025Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
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Published CVSS scores
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Attacks
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Technologies
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