How severe is CVE-2023-21554?

CVE-2023-21554 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-21554 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 95% (100th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-21554?

CVE-2023-21554 primarily affects Microsoft Windows 10 1607. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-21554?

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

When was CVE-2023-21554 published?

CVE-2023-21554 was published on 2023-04-11 and last updated on 2026-06-17.

CVE-2023-21554

CVE-2023-21554 is a critical-severity vulnerability in Microsoft Windows 10 1607 with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 95% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 95% (100th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Microsoft Windows 10 1607
Published: 2023-04-11
Last modified: 2026-06-17

Description

Microsoft Message Queuing (MSMQ) Remote Code Execution Vulnerability

Frequently asked questions

What is CVE-2023-21554?: Microsoft Message Queuing (MSMQ) Remote Code Execution Vulnerability
How severe is CVE-2023-21554?: CVE-2023-21554 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-21554 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 95% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-21554?: CVE-2023-21554 primarily affects Microsoft Windows 10 1607. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-21554?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2023-21554 published?: CVE-2023-21554 was published on 2023-04-11 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21554

Affected products (14)

cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_10_20h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_11_21h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_11_22h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:*:*
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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