CVE-2022-36338: Insyde INSYDEH2O

High severity, CVSS 8.2. EPSS: 0.5% chance of exploitation in the next 30 days.

An issue was discovered in Insyde InsydeH2O with kernel 5.0 through 5.5. An SMM callout vulnerability in the SMM driver FwBlockServiceSmm, creating SMM, leads to arbitrary code execution. An attacker can replace the pointer to the UEFI boot service GetVariable with a pointer to malware, and then generate a software SMI.

Affected products

• Insyde INSYDEH2O: from 5.0, up to and including 5.5

Published 2022-09-23. Last modified 2026-06-17.