CVE-2022-32266
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedDMA attacks on the parameter buffer used by a software SMI handler used by the driver PcdSmmDxe could lead to a TOCTOU attack on the SMI handler and lead to corruption of other ACPI fields and adjacent memory fields. DMA attacks on the parameter buffer used by a software SMI handler used by the driver PcdSmmDxe could lead to a TOCTOU attack on the SMI handler and lead to corruption of other ACPI fields and adjacent memory fields. The attack would require detailed knowledge of the PCD database contents on the current platform. This issue was discovered by Insyde engineering during a security review. This issue is fixed in Kernel 5.3: 05.36.23, Kernel 5.4: 05.44.23, Kernel 5.5: 05.52.23. Kernel 5.2 is unaffected. CWE-787 An issue was discovered in Insyde InsydeH2O with kernel 5.0 through 5.5. DMA attacks on the parameter buffer that is used by a software SMI handler (used by the PcdSmmDxe driver) could lead to a TOCTOU race-condition attack on the SMI handler, and lead to corruption of other ACPI fields and adjacent memory fields. The attack would require detailed knowledge of the PCD database contents on the current platform.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceDMA attacks on the parameter buffer used by the PcdSmmDxe driver's software SMI handler can exploit a TOCTOU (Time-of-Check-Time-of-Use) race condition. An attacker with knowledge of the PCD database can corrupt ACPI fields and adjacent memory by manipulating the buffer between the time of check and use in the SMI handler.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data>= 5.3, < 5.3.05.36.23>= 5.4, < 5.4.05.44.23>= 5.5, < 5.5.05.52.23CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- High
- Privileges
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify the Insyde Kernel versionCheck the system firmware/BIOS version information, typically displayed in the BIOS setup utility under 'Main' or 'System Information', or retrieve via `dmidecode -s bios-version` on Linux or `wmic bios get smbiosbiosversion` on WindowsAffected if The reported version falls within the ranges: 5.3.x where x < 05.36.23; 5.4.x where x < 05.44.23; or 5.5.x where x < 05.52.23
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Confirm the firmware vendor is InsydeCheck the BIOS vendor string via `dmidecode -s bios-vendor` on Linux or `wmic bios get manufacturer` on Windows, or view in BIOS setupAffected if The vendor is Insyde (InsydeH2O) and the version from step 1 is in the affected ranges
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Verify the PcdSmmDxe driver is presentCheck UEFI driver database or system firmware components for the PcdSmmDxe driver; on Linux, inspect /sys/firmware/efi/efivars/ or use uefidump tools if availableAffected if The PcdSmmDxe driver is loaded in the UEFI environment and the kernel version is vulnerable
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Confirm Software SMI handling is enabledCheck if SW SMI is enabled in BIOS settings (typically under 'Security' or 'Advanced' > 'Intel VT-d' or 'DMA Protection'); on Linux, verify with `dmesg | grep -i smi` or check ACPI tables for SMI-related entriesAffected if Software SMI handlers are active and the firmware version is in the affected ranges
The system is affected if it runs InsydeH2O BIOS with Kernel version 5.3.x below 05.36.23, 5.4.x below 05.44.23, or 5.5.x below 05.52.23, with the PcdSmmDxe driver present and SW SMI enabled.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped5.3.05.36.235.4.05.44.235.5.05.52.23
Update InsydeH2O kernel 5.0-5.5 to the fixed versions: 05.36.23 (Kernel 5.3), 05.44.23 (Kernel 5.4), or 05.52.23 (Kernel 5.5). Consider implementing DMA protection and memory isolation for SMI handler buffers.
Kernel 5.3: 05.36.23; Kernel 5.4: 05.44.23; Kernel 5.5: 05.52.23 (whichever is the next major version above the current installed version)
- Identify the current InsydeH2O kernel version by checking the UEFI firmware version on the affected system
- Navigate to the Insyde support portal or contact Insyde for the specific firmware update containing the fixed kernel version
- Download the firmware update for the appropriate kernel version (5.3.05.36.23, 5.4.05.44.23, or 5.5.05.52.23 depending on current version)
- Apply the firmware update through the vendor's recommended process, typically via a firmware flashing utility or through the UEFI BIOS update mechanism
- Verify the firmware update was applied successfully by checking the kernel version after reboot
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation8.0 h
- Implementation40.0 h
- Testing24.0 h
- Review / QA12.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2022-32266 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2022-32266 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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