Vulnerability-Lookup

MSRC_CVE-2021-33745

Vulnerability from csaf_microsoft - Published: 2021-07-13 07:00 - Updated: 2021-07-13 07:00

Summary

Windows DNS Server Denial of Service Vulnerability

Severity

Important

Notes

Additional Resources: To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

Disclaimer: The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.

Customer Action: Required. The vulnerability documented by this CVE requires customer action to resolve.

CVE-2021-33745

6.5 (Medium)


                
                  CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C

Affected products

Fixed 16 products

Product	Identifier	Version	Remediation
Windows Server 2008 for 32-bit Systems Service Pack 2 6.0.6003.21167 Windows Server 2008 for 32-bit Systems Service Pack 2		6.0.6003.21167
Windows Server 2008 for x64-based Systems Service Pack 2 6.0.6003.21167 Windows Server 2008 for x64-based Systems Service Pack 2		6.0.6003.21167
Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation) 6.0.6003.21167 Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation)		6.0.6003.21167
Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) 6.1.7601.25661 Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation)		6.1.7601.25661
Windows Server 2008 R2 for x64-based Systems Service Pack 1 6.1.7601.25661 Windows Server 2008 R2 for x64-based Systems Service Pack 1		6.1.7601.25661
Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation) 6.0.6003.21167 Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation)		6.0.6003.21167
Windows Server 2012 6.2.9200.23409 Windows Server 2012		6.2.9200.23409
Windows Server 2012 (Server Core installation) 6.2.9200.23409 Windows Server 2012 (Server Core installation)		6.2.9200.23409
Windows Server 2012 R2 6.3.9600.20069 Windows Server 2012 R2		6.3.9600.20069
Windows Server 2012 R2 (Server Core installation) 6.3.9600.20069 Windows Server 2012 R2 (Server Core installation)		6.3.9600.20069
Windows Server 2016 10.0.14393.4530 Windows Server 2016		10.0.14393.4530
Windows Server 2016 (Server Core installation) 10.0.14393.4530 Windows Server 2016 (Server Core installation)		10.0.14393.4530
Windows Server 2019 10.0.17763.2061 Windows Server 2019		10.0.17763.2061
Windows Server 2019 (Server Core installation) 10.0.17763.2061 Windows Server 2019 (Server Core installation)		10.0.17763.2061
Windows Server, version 2004 (Server Core installation) 10.0.19041.1110 Windows Server, version 2004 (Server Core installation)		10.0.19041.1110
Windows Server, version 20H2 (Server Core Installation) 10.0.19042.1110 Windows Server, version 20H2 (Server Core Installation)		10.0.19042.1110

Known affected 16 products

Product	Version	Remediation
Windows Server, version 20H2 (Server Core Installation) <10.0.19042.1110 Windows Server, version 20H2 (Server Core Installation)	<10.0.19042.1110	Vendor Fix fix
Windows Server, version 2004 (Server Core installation) <10.0.19041.1110 Windows Server, version 2004 (Server Core installation)	<10.0.19041.1110	Vendor Fix fix
Windows Server 2019 (Server Core installation) <10.0.17763.2061 Windows Server 2019 (Server Core installation)	<10.0.17763.2061	Vendor Fix fix
Windows Server 2019 <10.0.17763.2061 Windows Server 2019	<10.0.17763.2061	Vendor Fix fix
Windows Server 2016 (Server Core installation) <10.0.14393.4530 Windows Server 2016 (Server Core installation)	<10.0.14393.4530	Vendor Fix fix
Windows Server 2016 <10.0.14393.4530 Windows Server 2016	<10.0.14393.4530	Vendor Fix fix
Windows Server 2012 R2 (Server Core installation) <6.3.9600.20069 Windows Server 2012 R2 (Server Core installation)	<6.3.9600.20069	Vendor Fix fix Vendor Fix fix
Windows Server 2012 R2 <6.3.9600.20069 Windows Server 2012 R2	<6.3.9600.20069	Vendor Fix fix Vendor Fix fix
Windows Server 2012 (Server Core installation) <6.2.9200.23409 Windows Server 2012 (Server Core installation)	<6.2.9200.23409	Vendor Fix fix Vendor Fix fix
Windows Server 2012 <6.2.9200.23409 Windows Server 2012	<6.2.9200.23409	Vendor Fix fix Vendor Fix fix
Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation) <6.0.6003.21167 Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation)	<6.0.6003.21167	Vendor Fix fix Vendor Fix fix
Windows Server 2008 R2 for x64-based Systems Service Pack 1 <6.1.7601.25661 Windows Server 2008 R2 for x64-based Systems Service Pack 1	<6.1.7601.25661	Vendor Fix fix Vendor Fix fix
Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) <6.1.7601.25661 Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation)	<6.1.7601.25661	Vendor Fix fix Vendor Fix fix
Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation) <6.0.6003.21167 Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation)	<6.0.6003.21167	Vendor Fix fix Vendor Fix fix
Windows Server 2008 for x64-based Systems Service Pack 2 <6.0.6003.21167 Windows Server 2008 for x64-based Systems Service Pack 2	<6.0.6003.21167	Vendor Fix fix Vendor Fix fix
Windows Server 2008 for 32-bit Systems Service Pack 2 <6.0.6003.21167 Windows Server 2008 for 32-bit Systems Service Pack 2	<6.0.6003.21167	Vendor Fix fix Vendor Fix fix

Threats

Impact Denial of Service

Exploit Status Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Less Likely;Older Software Release:Exploitation Less Likely

References

7 references

URL	Category
https://msrc.microsoft.com/update-guide/vulnerabi…	self
https://msrc.microsoft.com/csaf/advisories/2021/m…	self
https://www.microsoft.com/en-us/msrc/exploitabili…	external
https://support.microsoft.com/lifecycle	external
https://www.first.org/cvss	external
https://msrc.microsoft.com/update-guide/vulnerabi…	self
https://msrc.microsoft.com/csaf/advisories/2021/m…	self

Acknowledgments

Ting Yu from CERT Team of Legendsec at Qi'anxin Group

ZhiyiZhang from Codesafe Team of Legendsec at Qi'anxin Group

JSON

To clipboard

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          "category": "vendor_fix",
          "date": "2021-07-13T07:00:00.000Z",
          "details": "6.0.6003.21167:Monthly Rollup:https://support.microsoft.com/help/5004305",
          "product_ids": [
            "16",
            "11",
            "15",
            "14"
          ],
          "url": "https://support.microsoft.com/help/5004305"
        },
        {
          "category": "vendor_fix",
          "date": "2021-07-13T07:00:00.000Z",
          "details": "6.0.6003.21167:Security Only:https://support.microsoft.com/help/5004299",
          "product_ids": [
            "16",
            "11",
            "15",
            "14"
          ],
          "url": "https://support.microsoft.com/help/5004299"
        },
        {
          "category": "vendor_fix",
          "date": "2021-07-13T07:00:00.000Z",
          "details": "6.1.7601.25661:Monthly Rollup:https://support.microsoft.com/help/5004289",
          "product_ids": [
            "12",
            "13"
          ],
          "url": "https://support.microsoft.com/help/5004289"
        },
        {
          "category": "vendor_fix",
          "date": "2021-07-13T07:00:00.000Z",
          "details": "6.1.7601.25661:Security Only:https://support.microsoft.com/help/5004307",
          "product_ids": [
            "12",
            "13"
          ],
          "url": "https://support.microsoft.com/help/5004307"
        },
        {
          "category": "vendor_fix",
          "date": "2021-07-13T07:00:00.000Z",
          "details": "6.2.9200.23409:Monthly Rollup:https://support.microsoft.com/help/5004294",
          "product_ids": [
            "10",
            "9"
          ],
          "url": "https://support.microsoft.com/help/5004294"
        },
        {
          "category": "vendor_fix",
          "date": "2021-07-13T07:00:00.000Z",
          "details": "6.2.9200.23409:Security Only:https://support.microsoft.com/help/5004302",
          "product_ids": [
            "10",
            "9"
          ],
          "url": "https://support.microsoft.com/help/5004302"
        },
        {
          "category": "vendor_fix",
          "date": "2021-07-13T07:00:00.000Z",
          "details": "6.3.9600.20069:Monthly Rollup:https://support.microsoft.com/help/5004298",
          "product_ids": [
            "8",
            "7"
          ],
          "url": "https://support.microsoft.com/help/5004298"
        },
        {
          "category": "vendor_fix",
          "date": "2021-07-13T07:00:00.000Z",
          "details": "6.3.9600.20069:Security Only:https://support.microsoft.com/help/5004285",
          "product_ids": [
            "8",
            "7"
          ],
          "url": "https://support.microsoft.com/help/5004285"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "environmentalScore": 0.0,
            "exploitCodeMaturity": "UNPROVEN",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "remediationLevel": "OFFICIAL_FIX",
            "reportConfidence": "CONFIRMED",
            "scope": "UNCHANGED",
            "temporalScore": 5.7,
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C",
            "version": "3.1"
          },
          "products": [
            "1",
            "2",
            "3",
            "4",
            "5",
            "6",
            "7",
            "8",
            "9",
            "10",
            "11",
            "12",
            "13",
            "14",
            "15",
            "16"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "details": "Denial of Service"
        },
        {
          "category": "exploit_status",
          "details": "Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Less Likely;Older Software Release:Exploitation Less Likely"
        }
      ],
      "title": "Windows DNS Server Denial of Service Vulnerability"
    }
  ]
}

CVE-2021-33745 (GCVE-0-2021-33745)

Vulnerability from cvelistv5 – Published: 2021-07-14 17:53 – Updated: 2026-08-10 15:11

Title

Windows DNS Server Denial of Service Vulnerability

Summary

Windows DNS Server Denial of Service Vulnerability

Severity

6.5 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C

CWE

Denial of Service

Assigner

microsoft mitre root Scorecard

References

2 references

URL	Tags
https://msrc.microsoft.com/update-guide/vulnerabi…	vendor-advisorypatch
https://portal.msrc.microsoft.com/en-US/security-…	x_refsource_MISCx_transferred

Impacted products

14 products

Vendor	Product	Version
Microsoft	Windows Server 2008 R2 Service Pack 1	Affected: 6.1.7601.0 , < 6.1.7601.25661 (custom)
Microsoft	Windows Server 2008 R2 Service Pack 1 (Server Core installation)	Affected: 6.1.7601.0 , < 6.1.7601.25661 (custom)
Microsoft	Windows Server 2008 Service Pack 2	Affected: 6.0.6003.0 , < 6.0.6003.21167 (custom)
Microsoft	Windows Server 2008 Service Pack 2 (Server Core installation)	Affected: 6.0.6003.0 , < 6.0.6003.21167 (custom)
Microsoft	Windows Server 2012	Affected: 6.2.9200.0 , < 6.2.9200.23409 (custom)
Microsoft	Windows Server 2012 (Server Core installation)	Affected: 6.2.9200.0 , < 6.2.9200.23409 (custom)
Microsoft	Windows Server 2012 R2	Affected: 6.3.9600.0 , < 6.3.9600.20069 (custom)
Microsoft	Windows Server 2012 R2 (Server Core installation)	Affected: 6.3.9600.0 , < 6.3.9600.20069 (custom)
Microsoft	Windows Server 2016	Affected: 10.0.14393.0 , < 10.0.14393.4530 (custom)
Microsoft	Windows Server 2016 (Server Core installation)	Affected: 10.0.14393.0 , < 10.0.14393.4530 (custom)
Microsoft	Windows Server 2019	Affected: 10.0.17763.0 , < 10.0.17763.2061 (custom)
Microsoft	Windows Server 2019 (Server Core installation)	Affected: 10.0.17763.0 , < 10.0.17763.2061 (custom)
Microsoft	Windows Server version 2004	Affected: 10.0.0 , < 10.0.19041.1110 (custom)
Microsoft	Windows Server version 20H2	Affected: 10.0.0 , < 10.0.19042.1110 (custom)

Date Public

2021-07-13 14:00

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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MSRC_CVE-2021-33745

CVE-2021-33745 (GCVE-0-2021-33745)

Tags

Sightings

Nomenclature

Related by attack behaviour