Vulnerability Intelligence Report
.NET Core and Visual Studio Denial of Service Vulnerability
CVE-2021-26423
.NET Core and Visual Studio Denial of Service Vulnerability
No Active Exploit Signals
CVSS Base Score
7.5
HIGH
Exploitability:3.9
Impact Score:3.6
EPSS Probability:3.86%
Executive Threat Verdict
Evaluating...
Evaluating Threat Landscape...
Assessing known weaponization, exploitation telemetry, and federal advisories.
Attack Surface
—
Authentication
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Weaponization
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SSVC Action
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Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| Microsoft | .NET 5.0 | 5.0.0 < 5.0.9 (affected) |
| Microsoft | .NET Core 2.1 | 2.1 < 2.1.30 (affected) |
| Microsoft | .NET Core 3.1 | 3.1 < 3.1.18 (affected) |
| Microsoft | Microsoft Visual Studio 2017 version 15.9 (includes 15.0 - 15.8) | 15.9.0 < 15.9.38 (affected) |
| Microsoft | Microsoft Visual Studio 2019 version 16.10 (includes 16.0 - 16.9) | 16.10.0 < 16.10.5 (affected) |
| Microsoft | Microsoft Visual Studio 2019 version 16.4 (includes 16.0 - 16.3) | 16.0 < 16.4.25 (affected) |
| Microsoft | Microsoft Visual Studio 2019 version 16.7 (includes 16.0 – 16.6) | 16.0.0 < 16.7.18 (affected) |
| Microsoft | Microsoft Visual Studio 2019 version 16.9 (includes 16.0 - 16.8) | 15.0.0 < 16.9.10 (affected) |
| Microsoft | PowerShell Core 7.0 | 7.0.0 < 7.0.7 (affected) |
| Microsoft | PowerShell Core 7.1 | 7.1.0 < 7.1.4 (affected) |
| Microsoft | Visual Studio 2019 for Mac version 8.10 | 8.1.0 < 8.10.7 (affected) |
References & Technical Advisories
No reference links found.
Threat Intelligence Signals
EPSS Score
3.858%
GitHub Advisory
Identity & Timeline
| Status | PUBLISHED |
| Assigning Authority | Microsoft Corporation · Vendor · USA |
| Reserved | 2021-01-29T00:00:00 |
| Published | 2021-08-12T18:11:31 |
| Patch Date | 2021-08-10 |
| Last Updated | 2026-08-10T15:09:59 |
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