How severe is CVE-2021-33745?

CVE-2021-33745 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 none, integrity none, and availability high.

Is CVE-2021-33745 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33745?

CVE-2021-33745 primarily affects Microsoft Windows Server 2008. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-33745?

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

When was CVE-2021-33745 published?

CVE-2021-33745 was published on 2021-07-14 and last updated on 2026-06-17.

CVE-2021-33745

CVE-2021-33745 is a medium-severity vulnerability in Microsoft Windows Server 2008 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.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.0
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Microsoft Windows Server 2008
Published: 2021-07-14
Last modified: 2026-06-17

Description

Windows DNS Server Denial of Service Vulnerability

Frequently asked questions

What is CVE-2021-33745?: Windows DNS Server Denial of Service Vulnerability
How severe is CVE-2021-33745?: CVE-2021-33745 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 none, integrity none, and availability high.
Is CVE-2021-33745 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33745?: CVE-2021-33745 primarily affects Microsoft Windows Server 2008. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-33745?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-33745 published?: CVE-2021-33745 was published on 2021-07-14 and last updated on 2026-06-17.

References

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-33745

Affected products (8)

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_2016:20h2:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2016:2004:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*

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