CVE-2021-43216

CVE-2021-43216 is a medium-severity vulnerability in Microsoft Windows 10 with a CVSS 3.x base score of 6.5. 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-668.

Key facts

• Severity: Medium (CVSS 3.x base score 6.5)
• CVSS v2: 6.8
• EPSS exploit prediction: 3% (87th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-668
• Affected product: Microsoft Windows 10
• Published: 2021-12-15
• Last modified: 2026-06-17

Description

Microsoft Local Security Authority (LSA) Server Information Disclosure Vulnerability

Frequently asked questions

What is CVE-2021-43216?

Microsoft Local Security Authority (LSA) Server Information Disclosure Vulnerability

How severe is CVE-2021-43216?

CVE-2021-43216 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-43216 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43216?

CVE-2021-43216 primarily affects Microsoft Windows 10. In total, 36 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-43216?

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

When was CVE-2021-43216 published?

CVE-2021-43216 was published on 2021-12-15 and last updated on 2026-06-17.

References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43216

Affected products (36)

• cpe:2.3:o:microsoft:windows_10:-:*:*:*:*:*:x64:*
• cpe:2.3:o:microsoft:windows_10:-:*:*:*:*:*: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_10:21h1:*:*:*:*:*:arm64:*
• cpe:2.3:o:microsoft:windows_10:21h1:*:*:*:*:*:x64:*
• cpe:2.3:o:microsoft:windows_10:21h1:*:*:*:*:*:x86:*
• 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_10:1909:*:*:*:*:*:arm64:*
• cpe:2.3:o:microsoft:windows_10:1909:*:*:*:*:*:x64:*
• cpe:2.3:o:microsoft:windows_10:1909:*:*:*:*:*:x86:*
• cpe:2.3:o:microsoft:windows_10:2004:*:*:*:*:*:arm64:*
• cpe:2.3:o:microsoft:windows_10:2004:*:*:*:*:*:x64:*
• cpe:2.3:o:microsoft:windows_10:2004:*:*:*:*:*:x86:*
• cpe:2.3:o:microsoft:windows_11:-:*:*:*:*:*:arm64:*
• cpe:2.3:o:microsoft:windows_11:-:*:*:*:*:*: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:20h2:*:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows_server:2022:*:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:*
• cpe:2.3:o:microsoft:windows_server_2008:r2:sp2:*:*:*:*:x64:*
• cpe:2.3:o:microsoft:windows_server_2008:r2:sp2:*:*:*:*:x86:*
• 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_2016:2004:*:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*

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