How severe is CVE-2023-21691?

CVE-2023-21691 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2023-21691 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-21691?

CVE-2023-21691 primarily affects Microsoft Windows 10 1507. In total, 28 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-21691?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-21691 published?

CVE-2023-21691 was published on 2023-02-14 and last updated on 2026-06-17.

CVE-2023-21691

CVE-2023-21691 is a high-severity vulnerability in Microsoft Windows 10 1507 with a CVSS 3.x base score of 7.5. 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-125.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Microsoft Windows 10 1507
Published: 2023-02-14
Last modified: 2026-06-17

Description

Microsoft Protected Extensible Authentication Protocol (PEAP) Information Disclosure Vulnerability

Frequently asked questions

What is CVE-2023-21691?: Microsoft Protected Extensible Authentication Protocol (PEAP) Information Disclosure Vulnerability
How severe is CVE-2023-21691?: CVE-2023-21691 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2023-21691 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-21691?: CVE-2023-21691 primarily affects Microsoft Windows 10 1507. In total, 28 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-21691?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-21691 published?: CVE-2023-21691 was published on 2023-02-14 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21691

Affected products (28)

cpe:2.3:o:microsoft:windows_10_1507:*:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10_1507:*:*:*:*:*:*: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_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_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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