CVE-2026-8863

CVE-2026-8863

High · published June 9, 2026

CVSS v3.1
7.8
EPSS
0%
Percentile
1.1
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.8 · HIGH
Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00106 · 1.1th percentile
Published
2026-06-09T18:10Z
EPSS history
Timeline
  • 09 JUN 18:10Z
    CVE-2026-8863
    cvelistv5