CVE-2021-26423

.NET Core and Visual Studio Denial of Service Vulnerability

CVSS v3 7.5 HIGH
CVSS v2.0 5.0 MEDIUM

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

5.0^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:N/C:N/I:N/A:P

Exploitability : 10.0 / Impact : 2.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact PARTIAL

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26423
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26423	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:microsoft:.net::::::::
	cpe:2.3:a:microsoft:.net_core::::::::
	cpe:2.3:a:microsoft:.net_core::::::::
	cpe:2.3:a:microsoft:powershell_core::::::::
	cpe:2.3:a:microsoft:powershell_core::::::::
	cpe:2.3:a:microsoft:visual_studio_2017::::::::
	cpe:2.3:a:microsoft:visual_studio_2019::::::::
	cpe:2.3:a:microsoft:visual_studio_2019:8.10:::::macos::

History

No history.

Information

Published : 2021-08-12 18:15

Updated : 2026-08-10 16:17

NVD link : CVE-2021-26423

Mitre link : CVE-2021-26423

CVE.ORG link : CVE-2021-26423

JSON object : View

Products Affected

microsoft

visual_studio_2017
powershell_core
.net
.net_core
visual_studio_2019

CWE

NVD-CWE-noinfo

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15.8)", "versions": [{"status": "affected", "version": "15.9.0", "lessThan": "15.9.38", "versionType": "custom"}]}, {"vendor": "Microsoft", "product": "Microsoft Visual Studio 2019 version 16.10 (includes 16.0 - 16.9)", "versions": [{"status": "affected", "version": "16.10.0", "lessThan": "16.10.5", "versionType": "custom"}]}, {"vendor": "Microsoft", "product": "Microsoft Visual Studio 2019 version 16.4 (includes 16.0 - 16.3)", "versions": [{"status": "affected", "version": "16.0", "lessThan": "16.4.25", "versionType": "custom"}]}, {"vendor": "Microsoft", "product": "Microsoft Visual Studio 2019 version 16.7 (includes 16.0 \u2013 16.6)", "versions": [{"status": "affected", "version": "16.0.0", "lessThan": "16.7.18", "versionType": "custom"}]}, {"vendor": "Microsoft", "product": "Microsoft Visual Studio 2019 version 16.9 (includes 16.0 - 16.8)", "versions": [{"status": "affected", "version": "15.0.0", "lessThan": "16.9.10", "versionType": "custom"}]}, {"vendor": "Microsoft", "product": "PowerShell Core 7.0", "versions": [{"status": "affected", "version": "7.0.0", "lessThan": "7.0.7", "versionType": "custom"}]}, {"vendor": "Microsoft", "product": "PowerShell Core 7.1", "versions": [{"status": "affected", "version": "7.1.0", "lessThan": "7.1.4", "versionType": "custom"}]}, {"vendor": "Microsoft", "product": "Visual Studio 2019 for Mac version 8.10", "versions": [{"status": "affected", "version": "8.1.0", "lessThan": "8.10.7", "versionType": "custom"}]}]}], "published": "2021-08-12T18:15:08.537", "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26423", "source": "secure@microsoft.com"}, {"url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26423", "tags": ["Patch", "Vendor Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": ".NET Core and Visual Studio Denial of Service Vulnerability"}, {"lang": "es", "value": "Una Vulnerabilidad de Denegaci\u00f3n de Servicio en .NET Core y Visual Studio"}], "lastModified": "2026-08-10T16:17:31.570", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:microsoft:.net:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B85CD4C7-D84B-4C54-A604-FC852038A565", "versionEndIncluding": "5.0.8", "versionStartIncluding": "5.0"}, {"criteria": "cpe:2.3:a:microsoft:.net_core:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FB624437-CB1B-46A2-BF75-30035D99D2EF", "versionEndIncluding": "2.1.28", "versionStartIncluding": "2.1"}, {"criteria": "cpe:2.3:a:microsoft:.net_core:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6F344BDC-2929-4CEA-8414-E4D07C1F76F0", "versionEndIncluding": "3.1.17", "versionStartIncluding": "3.1"}, {"criteria": "cpe:2.3:a:microsoft:powershell_core:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "BE4005F4-89BB-4597-9070-1137B4CEFC9B", "versionEndExcluding": "7.0.7", "versionStartIncluding": "7.0"}, {"criteria": "cpe:2.3:a:microsoft:powershell_core:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "40F33C0C-7AF0-4B48-828C-00534012D728", "versionEndExcluding": "7.1.4", "versionStartIncluding": "7.1"}, {"criteria": "cpe:2.3:a:microsoft:visual_studio_2017:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CE03B37D-72FE-4C25-BE62-9C422AEFC80E", "versionEndIncluding": "15.9", "versionStartIncluding": "15.0"}, {"criteria": "cpe:2.3:a:microsoft:visual_studio_2019:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "26472C42-CDB4-4176-B10B-3BF26F5030E3", "versionEndIncluding": "16.10", "versionStartIncluding": "16.0"}, {"criteria": "cpe:2.3:a:microsoft:visual_studio_2019:8.10:*:*:*:*:macos:*:*", "vulnerable": true, "matchCriteriaId": "BA547FFE-D557-4612-9840-EEE88ACF53AA"}], "operator": "OR"}]}], "sourceIdentifier": "secure@microsoft.com"}