Executive brief
InsydeH2O is firmware used in enterprise and embedded systems. A flaw in the UEFI boot verification process allows an attacker with high privileges to bypass secure boot mechanisms and execute arbitrary code during system startup, potentially compromising the entire system integrity before the operating system even loads.
Technical details
This vulnerability is a lack of verified boot (CWE-1277: Insufficient Verification of Data Authenticity in Firmware) in certain firmware volumes (FV) within the UEFI implementation. The attack requires high privilege access (PR:H) and does not require user interaction. An attacker with sufficient privileges can bypass secure boot verification on affected firmware versions, leading to arbitrary code execution during the boot phase. The issue affects multiple Intel processor families and InsydeH2O firmware; patched versions are available from Insyde Software.
Affected products
- Insyde InsydeH2O Multiple versions affected; patched versions available for various Intel platforms (Alder Lake, Raptor Lake, Arrow Lake, Meteor Lake, Elkhart Lake, and others)
Timeline
- 2026-08-11: disclosed
- 2026-08-12: advisory: CVE-2026-6484 published