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CVE Record

CVE-2021-43522: An issue was discovered in Insyde InsydeH2O with kernel 5.1 through 2021-11-08, 5.2 through 2021-11-08, and...

An issue was discovered in Insyde InsydeH2O with kernel 5.1 through 2021-11-08, 5.2 through 2021-11-08, and 5.3 through 2021-11-08. A StorageSecurityCommandDxe SMM memory corruption vulnerability allows an attacker to write fixed or predictable data to SMRAM. Exploiting this issue could lead to escalating privileges to SMM.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

This CVE affects InsydeH2O firmware used inside some hardware platforms. The flaw is in privileged firmware code and could let an attacker with enough local foothold escalate into System Management Mode, a highly trusted layer below the operating system. Business urgency depends on whether deployed devices embed the affected firmware versions.

Executive priority

Treat this as a high-priority firmware exposure review, not an emergency exploitation event. Focus first on platforms from vendors that confirm impact, then close firmware update gaps for business-critical systems.

Technical view

CVE-2021-43522 is an SMM memory corruption issue in InsydeH2O StorageSecurityCommandDxe affecting kernel 5.1, 5.2, and 5.3 builds through 2021-11-08. The CVE says fixed or predictable data can be written to SMRAM, potentially escalating privileges to SMM. Public severity and CVSS are not supplied in the bundle.

Likely exposure

Exposure is likely limited to systems whose OEM firmware uses affected InsydeH2O kernel versions. NetApp, Siemens, and CERT references show downstream vendor impact assessment matters. The bundle does not provide a complete product list, so asset-specific vendor confirmation is required.

Exploitation context

The bundle does not identify active exploitation, public exploit availability, or CISA KEV listing. The impact is serious because SMM compromise can undermine operating-system controls, but practical exploitation details and prerequisites are not established by the provided sources.

Researcher notes

Key evidence is the CVE description: StorageSecurityCommandDxe can write fixed or predictable data into SMRAM, enabling possible SMM privilege escalation. Missing details include CVSS, CWE, exploit maturity, affected OEM model list, and definitive remediation text in the provided bundle.

Mitigation direction

  • Inventory hardware and firmware that may include InsydeH2O.
  • Check OEM, Insyde, NetApp, Siemens, and CERT guidance for affected models.
  • Prioritize firmware updates where vendors identify affected products.
  • Use vendor-supported firmware only; avoid unofficial firmware packages.
  • Document unsupported systems and plan replacement or isolation.

Validation and detection

  • Confirm firmware vendor and InsydeH2O kernel version for each asset.
  • Compare versions against 5.1, 5.2, and 5.3 through 2021-11-08.
  • Review downstream vendor advisories for product-specific impact statements.
  • Verify firmware update status through vendor management tooling or asset records.
  • Track exceptions where vendors have not confirmed exposure.
Prepared
Confidence
medium
Sources
6

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

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CVE-2021-43522 mapping review

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
0Timeline events
0ADP providers
5Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/an/an/aListed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.