What is CVE-2020-0836?

A denial of service vulnerability exists in Windows DNS when it fails to properly handle queries. An attacker who successfully exploited this vulnerability could cause the DNS service to become nonresponsive. To exploit the vulnerability, an authenticated attacker could send malicious DNS queries to a target, resulting in a denial of service. The update addresses the vulnerability by correcting how Windows DNS processes queries.

How severe is CVE-2020-0836?

CVE-2020-0836 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 none, integrity none, and availability high.

Is CVE-2020-0836 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-0836?

CVE-2020-0836 primarily affects Microsoft Windows Server 2008. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-0836?

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-2020-0836 published?

CVE-2020-0836 was published on 2020-09-11 and last updated on 2026-06-17.

CVE-2020-0836

CVE-2020-0836 is a high-severity vulnerability in Microsoft Windows Server 2008 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.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 5% (91st percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Microsoft Windows Server 2008
Published: 2020-09-11
Last modified: 2026-06-17

Description

A denial of service vulnerability exists in Windows DNS when it fails to properly handle queries. An attacker who successfully exploited this vulnerability could cause the DNS service to become nonresponsive. To exploit the vulnerability, an authenticated attacker could send malicious DNS queries to a target, resulting in a denial of service. The update addresses the vulnerability by correcting how Windows DNS processes queries.

Frequently asked questions

What is CVE-2020-0836?: A denial of service vulnerability exists in Windows DNS when it fails to properly handle queries. An attacker who successfully exploited this vulnerability could cause the DNS service to become nonresponsive. To exploit the vulnerability, an authenticated attacker could send malicious DNS queries to a target, resulting in a denial of service. The update addresses the vulnerability by correcting how Windows DNS processes queries.
How severe is CVE-2020-0836?: CVE-2020-0836 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 none, integrity none, and availability high.
Is CVE-2020-0836 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-0836?: CVE-2020-0836 primarily affects Microsoft Windows Server 2008. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-0836?: 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-2020-0836 published?: CVE-2020-0836 was published on 2020-09-11 and last updated on 2026-06-17.

References

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0836

Affected products (9)

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_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_2016:1903:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2016:1909:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2016:2004:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*

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