How severe is CVE-2023-21560?

CVE-2023-21560 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over physical access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-21560 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-21560?

CVE-2023-21560 primarily affects Microsoft Windows 10 1607. In total, 31 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-21560?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-21560 published?

CVE-2023-21560 was published on 2023-01-10 and last updated on 2026-06-17.

CVE-2023-21560

CVE-2023-21560 is a medium-severity vulnerability in Microsoft Windows 10 1607 with a CVSS 3.x base score of 6.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-863.

Key facts

Severity: Medium (CVSS 3.x base score 6.6)
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: Microsoft Windows 10 1607
Published: 2023-01-10
Last modified: 2026-06-17

Description

Windows Boot Manager Security Feature Bypass Vulnerability

Frequently asked questions

What is CVE-2023-21560?: Windows Boot Manager Security Feature Bypass Vulnerability
How severe is CVE-2023-21560?: CVE-2023-21560 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over physical access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-21560 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-21560?: CVE-2023-21560 primarily affects Microsoft Windows 10 1607. In total, 31 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-21560?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-21560 published?: CVE-2023-21560 was published on 2023-01-10 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21560

Affected products (31)

cpe:2.3:o:microsoft:windows_10_1607:-:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10_1607:-:*:*:*:*:*:x86:*
cpe:2.3:o:microsoft:windows_10_1809:-:*:*:*:*:*:arm64:*
cpe:2.3:o:microsoft:windows_10_1809:-:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10_1809:-:*:*:*:*:*:x86:*
cpe:2.3:o:microsoft:windows_10_20h2:-:*:*:*:*:*:arm64:*
cpe:2.3:o:microsoft:windows_10_20h2:-:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10_20h2:-:*:*:*:*:*:x86:*
cpe:2.3:o:microsoft:windows_10_21h2:-:*:*:*:*:*:arm64:*
cpe:2.3:o:microsoft:windows_10_21h2:-:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10_21h2:-:*:*:*:*:*:x86:*
cpe:2.3:o:microsoft:windows_10_22h2:-:*:*:*:*:*:arm64:*
cpe:2.3:o:microsoft:windows_10_22h2:-:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10_22h2:-:*:*:*:*:*:x86:*
cpe:2.3:o:microsoft:windows_11_21h2:-:*:*:*:*:*:arm64:*
cpe:2.3:o:microsoft:windows_11_21h2:-:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_11_22h2:-:*:*:*:*:*:arm64:*
cpe:2.3:o:microsoft:windows_11_22h2:-:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_7:-:sp1:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_7:-:sp1:*:*:*:*:x86:*
cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:*:*:x86:*
cpe:2.3:o:microsoft:windows_rt_8.1:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:x86:*
cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2016:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2022:-:*:*:*:*:*:*:*

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