.NET Core
CVE-2020-1108 — .NET Core & .NET Framework Denial of Service Vulnerability
Executive Summary
A denial of service vulnerability exists when .NET Core or .NET Framework improperly handles web requests. An attacker who successfully exploited this vulnerability could cause a denial of service against a .NET Core or .NET Framework web application. The vulnerability can be exploited remotely, without authentication. A remote unauthenticated attacker could exploit this vulnerability by issuing specially crafted requests to the .NET Core or .NET Framework application. The update addresses the vulnerability by correcting how the .NET Core or .NET Framework web application handles web requests.
Overview
7.5
CVSS HIGH
Important
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
ATTACK VECTOR
Network
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
None
USER INTERACTION
None
SCOPE
Unchanged
EPSS Score
0.11684
probability of exploitation in the next 30 days
0.95514 percentile - updated 2026-06-21
View on FIRST.org
Affected Products
51 affected products
| Product | KB Article | Severity | Impact | Restart Required |
|---|---|---|---|---|
| .NET 5.0 | Release Notes (Security Update) |
Important | Denial of Service | Maybe |
| .NET Core 2.1 | Release Notes (Security Update) |
Important | Denial of Service | Maybe |
| .NET Core 3.1 | Release Notes (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 2.0 Service Pack 2 on Windows Server 2008 for 32-bit Systems Service Pack 2 4556402 (Monthly Rollup) 4556406 (Security Only) Important Denial of Service 4533098; 4535105 Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 2.0 Service Pack 2 on Windows Server 2008 for x64-based Systems Service Pack 2 4556402 (Monthly Rollup) 4556406 (Security Only) Important Denial of Service 4533098; 4535105 Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 3.0 Service Pack 2 on Windows Server 2008 for 32-bit Systems Service Pack 2 4556402 (Monthly Rollup) 4556406 (Security Only) Important Denial of Service 4533098; 4535105 Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 3.0 Service Pack 2 on Windows Server 2008 for x64-based Systems Service Pack 2 4556402 (Monthly Rollup) 4556406 (Security Only) Important Denial of Service 4533098; 4535105 Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 on Windows 10 Version 1607 for 32-bit Systems | 4556813 (Security Update) |
Important | Denial of Service | Yes |
| Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 on Windows 10 Version 1607 for x64-based Systems | 4556813 (Security Update) |
Important | Denial of Service | Yes |
| Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2016 | 4556813 (Security Update) |
Important | Denial of Service | Yes |
| Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2016 (Server Core installation) | 4556813 (Security Update) |
Important | Denial of Service | Yes |
| Microsoft .NET Framework 3.5 AND 4.6/4.6.1/4.6.2 on Windows 10 for 32-bit Systems | 4556826 (Security Update) |
Important | Denial of Service | Yes |
| Microsoft .NET Framework 3.5 AND 4.6/4.6.1/4.6.2 on Windows 10 for x64-based Systems | 4556826 (Security Update) |
Important | Denial of Service | Yes |
| Microsoft .NET Framework 3.5 AND 4.7.1/4.7.2 on Windows 10 Version 1709 for 32-bit Systems | 4556812 (Security Update) |
Important | Denial of Service | Yes |
| Microsoft .NET Framework 3.5 AND 4.7.1/4.7.2 on Windows 10 Version 1709 for ARM64-based Systems | 4556812 (Security Update) |
Important | Denial of Service | Yes |
| Microsoft .NET Framework 3.5 AND 4.7.1/4.7.2 on Windows 10 Version 1709 for x64-based Systems | 4556812 (Security Update) |
Important | Denial of Service | Yes |
| Microsoft .NET Framework 3.5 AND 4.7.2 on Windows 10 Version 1803 for 32-bit Systems | 4556807 (Security Update) |
Important | Denial of Service | Yes |
| Microsoft .NET Framework 3.5 AND 4.7.2 on Windows 10 Version 1803 for ARM64-based Systems | 4556807 (Security Update) |
Important | Denial of Service | Yes |
| Microsoft .NET Framework 3.5 AND 4.7.2 on Windows 10 Version 1803 for x64-based Systems | 4556807 (Security Update) |
Important | Denial of Service | Yes |
| Microsoft .NET Framework 3.5 AND 4.7.2 on Windows 10 Version 1809 for 32-bit Systems | 4556441 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.7.2 on Windows 10 Version 1809 for ARM64-based Systems | 4556441 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.7.2 on Windows 10 Version 1809 for x64-based Systems | 4556441 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.7.2 on Windows Server 2019 | 4556441 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.7.2 on Windows Server 2019 (Server Core installation) | 4556441 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.7.2 on Windows Server, version 1803 (Server Core Installation) | 4556807 (Security Update) |
Important | Denial of Service | Yes |
| Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1809 for 32-bit Systems | 4556441 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1809 for x64-based Systems | 4556441 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1903 for 32-bit Systems | 4552931 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1903 for ARM64-based Systems | 4552931 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1903 for x64-based Systems | 4552931 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1909 for 32-bit Systems | 4552931 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1909 for ARM64-based Systems | 4552931 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1909 for x64-based Systems | 4552931 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.8 on Windows Server 2019 | 4556441 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.8 on Windows Server 2019 (Server Core installation) | 4556441 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.8 on Windows Server, version 1903 (Server Core installation) | 4552931 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 AND 4.8 on Windows Server, version 1909 (Server Core installation) | 4552931 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 3.5 on Windows 8.1 for 32-bit systems 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 3.5 on Windows 8.1 for x64-based systems 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 3.5 on Windows Server 2012 4556400 (Monthly Rollup) 4556404 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 3.5 on Windows Server 2012 (Server Core installation) 4556400 (Monthly Rollup) 4556404 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 3.5 on Windows Server 2012 R2 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 3.5 on Windows Server 2012 R2 (Server Core installation) 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 3.5.1 on Windows 7 for 32-bit Systems Service Pack 1 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 3.5.1 on Windows 7 for x64-based Systems Service Pack 1 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 3.5.1 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.5.2 on Windows 7 for 32-bit Systems Service Pack 1 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.5.2 on Windows 7 for x64-based Systems Service Pack 1 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.5.2 on Windows 8.1 for 32-bit systems 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.5.2 on Windows 8.1 for x64-based systems 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.5.2 on Windows RT 8.1 | 4556401 (Monthly Rollup) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 4.5.2 on Windows Server 2008 for 32-bit Systems Service Pack 2 4556402 (Monthly Rollup) 4556406 (Security Only) Important Denial of Service 4533098; 4535105 Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.5.2 on Windows Server 2008 for x64-based Systems Service Pack 2 4556402 (Monthly Rollup) 4556406 (Security Only) Important Denial of Service 4533098; 4535105 Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.5.2 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.5.2 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.5.2 on Windows Server 2012 4556400 (Monthly Rollup) 4556404 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.5.2 on Windows Server 2012 (Server Core installation) 4556400 (Monthly Rollup) 4556404 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.5.2 on Windows Server 2012 R2 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.5.2 on Windows Server 2012 R2 (Server Core installation) 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.6 on Windows Server 2008 for 32-bit Systems Service Pack 2 4556402 (Monthly Rollup) 4556406 (Security Only) Important Denial of Service 4533098; 4535105 Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.6 on Windows Server 2008 for x64-based Systems Service Pack 2 4556402 (Monthly Rollup) 4556406 (Security Only) Important Denial of Service 4533098; 4535105 Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows 7 for 32-bit Systems Service Pack 1 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows 7 for x64-based Systems Service Pack 1 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows 8.1 for 32-bit systems 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows 8.1 for x64-based systems 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows RT 8.1 | 4556401 (Monthly Rollup) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2012 4556400 (Monthly Rollup) 4556404 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2012 (Server Core installation) 4556400 (Monthly Rollup) 4556404 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2012 R2 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2012 R2 (Server Core installation) 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.8 on Windows 10 Version 1607 for 32-bit Systems | 4552926 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 4.8 on Windows 10 Version 1607 for x64-based Systems | 4552926 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 4.8 on Windows 10 Version 1709 for 32-bit Systems | 4552928 (Security Update) |
Important | Denial of Service | Unknown |
| Microsoft .NET Framework 4.8 on Windows 10 Version 1709 for x64-based Systems | 4552928 (Security Update) |
Important | Denial of Service | Unknown |
| Microsoft .NET Framework 4.8 on Windows 10 Version 1803 for 32-bit Systems | 4552929 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 4.8 on Windows 10 Version 1803 for x64-based Systems | 4552929 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 4.8 on Windows 7 for 32-bit Systems Service Pack 1 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.8 on Windows 7 for x64-based Systems Service Pack 1 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.8 on Windows 8.1 for 32-bit systems 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.8 on Windows 8.1 for x64-based systems 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.8 on Windows RT 8.1 | 4556401 (Monthly Rollup) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 4.8 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.8 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) 4556399 (Monthly Rollup) 4556403 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.8 on Windows Server 2012 4556400 (Monthly Rollup) 4556404 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.8 on Windows Server 2012 (Server Core installation) 4556400 (Monthly Rollup) 4556404 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.8 on Windows Server 2012 R2 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.8 on Windows Server 2012 R2 (Server Core installation) 4556401 (Monthly Rollup) 4556405 (Security Only) Important Denial of Service Base: N/A Temporal: N/A Vector: N/A Maybe None Microsoft .NET Framework 4.8 on Windows Server 2016 | 4552926 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 4.8 on Windows Server 2016 (Server Core installation) | 4552926 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft .NET Framework 4.8 on Windows Server, version 1803 (Server Core Installation) | 4552929 (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft Visual Studio 2017 version 15.9 (includes 15.0 - 15.8) | Release Notes (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft Visual Studio 2019 version 16.0 | Release Notes (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft Visual Studio 2019 version 16.4 (includes 16.0 - 16.3) | Release Notes (Security Update) |
Important | Denial of Service | Maybe |
| Microsoft Visual Studio 2019 version 16.5 | Release Notes (Security Update) |
Important | Denial of Service | Maybe |
| PowerShell 7.0 | Release Notes (Security Update) |
Important | Denial of Service | Maybe |
| PowerShell Core 6.2 | Release Notes (Security Update) |
Important | Denial of Service | Maybe |
Patches
11 patches
| Article | Type | Restart |
|---|---|---|
Release Notes |
Security Update | Maybe |
4556813 |
Security Update | Yes |
4556826 |
Security Update | Yes |
4556812 |
Security Update | Yes |
4556807 |
Security Update | Yes |
4556441 |
Security Update | Maybe |
4552931 |
Security Update | Maybe |
4556401 |
Monthly Rollup | Maybe |
4552926 |
Security Update | Maybe |
4552928 |
Security Update | Unknown |
4552929 |
Security Update | Maybe |
Known Exploits
No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.
Acknowledgments
Microsoft has not published researcher acknowledgments for this CVE, or they are not yet reflected in our data source. Check the MSRC advisory directly for the most current credit information.
References
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