SB20260415123 - Multiple vulnerabilities in Microsoft UEFI Secure Boot



SB20260415123 - Multiple vulnerabilities in Microsoft UEFI Secure Boot

Published: April 15, 2026

Security Bulletin ID SB20260415123
Severity
Low
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Local access
Highest impact Code execution

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 secuirty vulnerabilities.


1) Reliance on Untrusted Inputs in a Security Decision (CVE-ID: CVE-2026-0390)

The vulnerability allows a local user to compromise the target system.

The vulnerability exists due to reliance on untrusted input for a security decision in UEFI Secure Boot. A local administrator can bypass authentication feature and cause impersonation.


2) Improper access control (CVE-ID: CVE-2026-32220)

The vulnerability allows a local user to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to improper access restrictions in UEFI Secure Boot. A local administrator can bypass the Virtualization-based Security feature.


Remediation

Install update from vendor's website.