CVE-2020-0689 — Microsoft Secure Boot Security Feature Bypass Vulnerability

Executive Summary

A security feature bypass vulnerability exists in secure boot. An attacker who successfully exploited the vulnerability can bypass secure boot and load untrusted software. To exploit the vulnerability, an attacker could run a specially crafted application. The security update addresses the vulnerability by blocking vulnerable third-party bootloaders. For further information see Security update for Secure Boot DBX: January 12, 2021 .

Overview

6.7

CVSS MEDIUM

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Security Feature Bypass

Released Feb 11 2020

Last Updated Feb 11 2020

Publicly Disclosed Yes

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.01048 — 0.59742 percentile

NVD CVSS 6.7 MEDIUM — differs from MSRC

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C

ATTACK VECTOR

Local

ATTACK COMPLEXITY

Low

PRIVILEGES REQUIRED

High

USER INTERACTION

None

SCOPE

Unchanged

CONFIDENTIALITY

High

INTEGRITY

High

AVAILABILITY

High

EXPLOIT CODE MATURITY

Functional

REMEDIATION LEVEL

Official Fix

REPORT CONFIDENCE

Confirmed

Temporal Score: 7.6

EPSS Score

0.01048

probability of exploitation in the next 30 days

0.59742 percentile - updated 2026-06-21

View on FIRST.org

Affected Products

16 affected products

Product	KB Article	Severity	Impact	Restart Required
Windows 10 for x64-based Systems	`5012170 (Security Update)`	Important	Security Feature Bypass	Maybe
Windows 10 Version 1607 for x64-based Systems	`5012170 (Security Update)`	Important	Security Feature Bypass	Maybe
Windows 10 Version 1803 for x64-based Systems	`4535680 (Security Update)`	Important	Security Feature Bypass	Yes
Windows 10 Version 1809 for x64-based Systems	`5012170 (Security Update)`	Important	Security Feature Bypass	Maybe
Windows 10 Version 1909 for x64-based Systems	`4535680 (Security Update)`	Important	Security Feature Bypass	Yes
Windows 8.1 for x64-based systems	`5012170 (Security Update)`	Important	Security Feature Bypass	Maybe
Windows Server 2012	`5012170 (Security Update)`	Important	Security Feature Bypass	Maybe
Windows Server 2012 (Server Core installation)	`5012170 (Security Update)`	Important	Security Feature Bypass	Maybe
Windows Server 2012 R2	`5012170 (Security Update)`	Important	Security Feature Bypass	Maybe
Windows Server 2012 R2 (Server Core installation)	`5012170 (Security Update)`	Important	Security Feature Bypass	Maybe
Windows Server 2016	`5012170 (Security Update)`	Important	Security Feature Bypass	Maybe
Windows Server 2016 (Server Core installation)	`5012170 (Security Update)`	Important	Security Feature Bypass	Maybe
Windows Server 2019	`5012170 (Security Update)`	Important	Security Feature Bypass	Maybe
Windows Server 2019 (Server Core installation)	`5012170 (Security Update)`	Important	Security Feature Bypass	Maybe
Windows Server, version 1803 (Server Core Installation)	`4535680 (Security Update)`	Important	Security Feature Bypass	Yes
Windows Server, version 1909 (Server Core installation)	`4535680 (Security Update)`	Important	Security Feature Bypass	Yes

Patches

2 patches

Article	Type	Restart
`5012170`	Security Update	Maybe
`4535680`	Security Update	Yes

Known Exploits

No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.

Acknowledgments

None

References

MSRC Advisory MITRE NVD