What’s Vulnerable › Vulnerabilities

CVE-2021-41838

• Severity: high (CVSS 8.2 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2022-02-03 · updated 2026-08-11
• Weakness: CWE-119

Description

An issue was discovered in SdHostDriver in the kernel 5.0 through 5.5 in Insyde InsydeH2O. There is an SMM callout that allows an attacker to access the System Management Mode and execute arbitrary code. This occurs because of a Numeric Range Comparison Without a Minimum Check.

Affected products

• Insydeh2O: from 5.1 before 5.16.42; from 5.2 before 5.26.42; from 5.3 before 5.35.42; from 5.4 before 5.43.42; from 5.5 before 5.51.42 — fixed in 5.16.42, 5.26.42, 5.35.42, 5.43.42, 5.51.42
• Siemens Simatic Field Pg M5 Firmware: all versions
• Siemens Simatic Field Pg M6 Firmware: all versions
• Siemens Simatic Ipc127E Firmware: all versions
• Siemens Simatic Ipc227G Firmware: all versions
• Siemens Simatic Ipc277G Firmware: all versions
• Siemens Simatic Ipc327G Firmware: all versions
• Siemens Simatic Ipc377G Firmware: all versions
• Siemens Simatic Ipc427E Firmware: all versions
• Siemens Simatic Ipc477E Firmware: all versions
• Siemens Simatic Ipc627E Firmware: all versions
• Siemens Simatic Ipc647E Firmware: all versions
• Siemens Simatic Ipc677E Firmware: all versions
• Siemens Simatic Ipc847E Firmware: all versions
• Siemens Simatic Itp1000 Firmware: all versions

How to fix

Upgrade to a fixed version: Insydeh2O 5.16.42, 5.26.42, 5.35.42, 5.43.42. Check the vendor advisory for mitigations.

References

• https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf
• https://security.netapp.com/advisory/ntap-20220222-0001/
• https://www.insyde.com/security-pledge
• https://www.insyde.com/security-pledge/SA-2022023
• https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdf
• https://security.netapp.com/advisory/ntap-20220222-0001/
• https://www.insyde.com/security-pledge
• https://www.insyde.com/security-pledge/SA-2022023
• https://www.kb.cert.org/vuls/id/796611
• https://cert-portal.siemens.com/productcert/html/ssa-306654.html

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