Privilege escalation via DMA command-buffer race
Published Feb 15, 2023 · Updated May 5, 2025
A TOCTOU race in IhisiSmm in Insyde InsydeH2O kernel 5.0 through 5.5 allows local users to corrupt SMRAM or elevate privileges. The IhisiDxe driver validates parameters in a shared IHISI command buffer, then reuses the buffer without preventing DMA changes before use. Successful exploitation requires local high privileges and precise timing; altered values can cause SMM code to modify protected SMRAM or operating-system memory.
Summary
What happened
A TOCTOU race in IhisiSmm in Insyde InsydeH2O kernel 5.0 through 5.5 allows local users to corrupt SMRAM or elevate privileges. The IhisiDxe driver validates parameters in a shared IHISI command buffer, then reuses the buffer without preventing DMA changes before use. Successful exploitation requires local high privileges and precise timing; altered values can cause SMM code to modify protected SMRAM or operating-system memory.
The record
- CVE
- CVE-2022-32471
- Published
- Feb 15, 2023
- Updated
- May 5, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-367, T1068
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Feb 15, 2023CVE publishedPublication date reported by the CVE source.
- May 5, 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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