SMM code execution via unchecked write address
Published Sep 23, 2022 · Updated May 5, 2025
Memory corruption in InsydeH2O kernel 5.0 through 5.5 allows local users with high privileges to execute code in SMM. The FvbServicesRuntimeDxe SMI handler passes an attacker-controlled address to FwBlockServiceSmm write routines without checking whether it points into SMRAM. Runtime code with high privileges can trigger fixed or controlled byte writes that corrupt SMI code or SMRAM maps and gain ring -2 execution.
Summary
What happened
Memory corruption in InsydeH2O kernel 5.0 through 5.5 allows local users with high privileges to execute code in SMM. The FvbServicesRuntimeDxe SMI handler passes an attacker-controlled address to FwBlockServiceSmm write routines without checking whether it points into SMRAM. Runtime code with high privileges can trigger fixed or controlled byte writes that corrupt SMI code or SMRAM maps and gain ring -2 execution.
The record
- CVE
- CVE-2022-35893
- Published
- Sep 23, 2022
- Updated
- May 5, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-20, T1068
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Sep 23, 2022CVE publishedPublication date reported by the CVE source.
- May 5, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
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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