CVE-2019-20908: An issue was discovered in drivers/firmware/efi/efi.c in the Linux kernel before 5.4.

Security readout for executives and security teams

This Linux kernel flaw can weaken Secure Boot or kernel lockdown protections by allowing misuse of an EFI ACPI variable. On systems relying on those controls to prevent untrusted kernel code, impact can be significant. The bundle does not provide CVSS scoring or evidence of active exploitation. Exposure is most relevant to Linux systems using EFI, Secure Boot, or kernel lockdown, especially kernels before 5.4 and vendor-maintained older kernel branches referenced by Ubuntu and openSUSE advisories. Treat as high priority for Secure Boot or lockdown-dependent systems because it weakens a core platform integrity control. It is less urgent for systems where those controls are not used, but still warrants normal kernel security patching. Mitigation focus: Update affected Linux kernels using vendor advisories and supported package channels.; Prioritize systems relying on Secure Boot or lockdown for trust enforcement.; Review Ubuntu USN-4426-1, USN-4427-1, USN-4439-1, USN-4440-1, and openSUSE guidance..

Prepared

Jun 3, 2026, 10:59 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.