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Vulnerability record · CVE-2021-42554 · published 3 February 2022

CVE-2021-42554: Insydeh2o out-of-bounds write vulnerability

Insyde · Insydeh2o

An issue was discovered in Insyde InsydeH2O with Kernel 5.0 before 05.08.42, Kernel 5.1 before 05.16.42, Kernel 5.2 before 05.26.42, Kernel 5.3 before 05.35.42, Kernel 5.4 before 05.42.51, and Kernel 5.5 before 05.50.51. An SMM memory corruption vulnerability in FvbServicesRuntimeDxe allows a possible attacker to write fixed or predictable data to SMRAM. Exploiting this issue could lead to escalating privileges to SMM.

8.2 CVSS 3.1 High EPSS 0.33% · top 76.7% CWE-787 · Out-of-bounds write
8.2CVSS 3.1 base score, v2 7.2
0.33%EPSS exploitation probability, 30 days
NoNot in CISA KEV
16Affected product versions listed by NVD
10References
11 Aug 2026Last modified by NVD

Description

An issue was discovered in Insyde InsydeH2O with Kernel 5.0 before 05.08.42, Kernel 5.1 before 05.16.42, Kernel 5.2 before 05.26.42, Kernel 5.3 before 05.35.42, Kernel 5.4 before 05.42.51, and Kernel 5.5 before 05.50.51. An SMM memory corruption vulnerability in FvbServicesRuntimeDxe allows a possible attacker to write fixed or predictable data to SMRAM. Exploiting this issue could lead to escalating privileges to SMM.

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

Affected products

16 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf Third Party Advisory
https://security.netapp.com/advisory/ntap-20220216-0007/ Third Party Advisory
https://www.insyde.com/security-pledge Vendor Advisory
https://www.insyde.com/security-pledge/SA-2022012 Vendor Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf Third Party Advisory
https://security.netapp.com/advisory/ntap-20220216-0007/ Third Party Advisory
https://www.insyde.com/security-pledge Vendor Advisory
https://www.insyde.com/security-pledge/SA-2022012 Vendor Advisory
https://www.kb.cert.org/vuls/id/796611
https://cert-portal.siemens.com/productcert/html/ssa-306654.html

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Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-42554), CISA KEV, FIRST EPSS (scores of 2026-09-29). This page is refreshed as NVD updates the record.