7.5

CVE-2021-43522: insyde insydeh2o Out-of-bounds Write

CVSS: 7.5v3.1HighModified
Published 02-02-2022Last modified 11-08-2026
Open JSON

Vulnerability summary

CVE-2021-43522 is a high (CVSS 7.5) Out-of-bounds Write vulnerability in insyde insydeh2o. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 17.2% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (NVD)
EPSS score
0.26%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 02-02-2022
    PublishedVulnerability first disclosed.
  2. 11-08-2026
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

2 scores · 1 source · 2 versions

EPSS trend

Probability

0.26%

Chance of exploitation in the next 30 days

Percentile

17%

Versus all other CVEs

30-day change

0.00 pp

From 0.26% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.26%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Insyde1 product
  • insydeh2o≥ 5.1, < 5.14.34 | ≥ 5.2, < 5.24.34 | ≥ 5.3, < 5.33.34

1 vendor · 1 product

References

5 links