CVE-2020-14372

Secure Boot bypass via unrestricted ACPI command

Published Mar 3, 2021 · Updated Aug 4, 2024

Security feature bypass in GNU GRUB before 2.06 allows local users with root privileges to disable Linux kernel lockdown. The acpi command remains enabled under UEFI Secure Boot and loads a crafted SSDT that overwrites the kernel lockdown variable in memory. Exploitation requires root access plus changes to /boot/efi and grub.cfg, after which unsigned kernel modules or kexec code can run.

CVSS severity7.5
High
EPSS probability1.74%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Security feature bypass in GNU GRUB before 2.06 allows local users with root privileges to disable Linux kernel lockdown. The acpi command remains enabled under UEFI Secure Boot and loads a crafted SSDT that overwrites the kernel lockdown variable in memory. Exploitation requires root access plus changes to /boot/efi and grub.cfg, after which unsigned kernel modules or kexec code can run.

The record

CVE
CVE-2020-14372
Published
Mar 3, 2021
Updated
Aug 4, 2024
Vendor
The GnuPG Project
Product
GNU GRUB
Classifications
CWE-184, T1553.006
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Mar 3, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=grub 2.06

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

The GnuPG Project · GNU GRUBversion=grub 2.06

Published CVSS scores

7.5CanonicalCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-184Incomplete List of Disallowed Inputs
T1553.006Code Signing Policy Modification

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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