CVE-2021-38578: Insyde Kernel

Critical severity, CVSS 9.8. EPSS: 1% chance of exploitation in the next 30 days.

Existing CommBuffer checks in SmmEntryPoint will not catch underflow when computing BufferSize.

Affected products

• Insyde Kernel: version 5.0 only; version 5.1 only; version 5.2 only; version 5.3 only; version 5.4 only; version 5.5 only
• Tianocore EDK2: up to and including 202202

Published 2022-03-03. Last modified 2026-06-17.