CVE-2020-5955: Insyde INSYDEH2O UEFI BIOS

Critical severity, CVSS 9.8. EPSS: 1.4% chance of exploitation in the next 30 days.

An issue was discovered in Int15MicrocodeSmm in Insyde InsydeH2O before 2021-10-14 on Intel client chipsets. A caller may be able to escalate privileges.

Affected products

• Insyde INSYDEH2O UEFI BIOS: before 05.32.30.0001 (fixed in 05.32.30.0001); before 05.41.35.0001 (fixed in 05.41.35.0001); before 05.42.11.0026 (fixed in 05.42.11.0026); before 05.04.21.0068 (fixed in 05.04.21.0068); before 05.42.09.0003 (fixed in 05.42.09.0003); before 05.21.51.0040 (fixed in 05.21.51.0040); …

Published 2021-11-03. Last modified 2026-06-17.