CVE-2021-33626 — Security Box Score

CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2021-33626HIGH

n/a n/a — A vulnerability exists in SMM (System Management Mode) branch that registers a SWSMI handler that does not sufficiently check or validate…

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   L   L   L   N  U  H  H  H    7.8   .0031   23.5     —

AFFECTED
  Product  Versions  Fixed
  n/a      n/a –     —

TIMELINE
  May 28  Reserved by mitre
  Oct 1   Published (CNA: mitre)
  Aug 11  ENRICHED — CVE-2021-33626. Received CVSS 7.8 and CPE data from NVD.

CWE-829 · CNA: mitre · CVSS v3.1 · 6 references · NVD status: Modified

Description

A vulnerability exists in SMM (System Management Mode) branch that registers a SWSMI handler that does not sufficiently check or validate the allocated buffer pointer(QWORD values for CommBuffer). This can be used by an attacker to corrupt data in SMRAM memory and even lead to arbitrary code execution.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
May 28, 2021	Reserved	Reserved by mitre
October 1, 2021	Published	Published (CNA: mitre)
August 11, 2026	ENRICHED	ENRICHED — CVE-2021-33626. Received CVSS 7.8 and CPE data from NVD.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
n/a	n/a	—	n/a	—

Weaknesses

CWE-829

References (6)

https://cert-portal.siemens.com/productcert/html/ssa-306654.html
https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf [Third Party Advisory]
https://security.netapp.com/advisory/ntap-20220216-0006/ [Third Party Advisory]
https://www.insyde.com/security-pledge [Vendor Advisory]
https://www.insyde.com/security-pledge/SA-2021001 [Vendor Advisory]
https://www.kb.cert.org/vuls/id/796611

Authoritative record: CVE-2021-33626 at cve.org

Weaknesses: CWE-829

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2021-33626 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.