VULNERABILITY INTELLIGENCE
CVE-2026-8863
CVSS score7.8 HIGH
EPSS probability0.11%
CISA KEVNot currently listed
Published2026-06-09
Last modified2026-07-23
CVSS vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Description
Multiple Microsoft-sigend UEFI SHIM bootloaders are vulnerable to SecureBoot bypass. An attacker with administrative privileges or the ability to modify the boot process could use one of the vulnerable shim bootloaders to bypass Secure Boot protections and execute arbitrary code before the operating system loads. Specific UEFI DBX update is required to block these vulnerable boot loaders.