CVE-2019-0820

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 5.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-05-16 · updated 2026-06-17
Weakness: CWE-400

Description

A denial of service vulnerability exists when .NET Framework and .NET Core improperly process RegEx strings, aka '.NET Framework and .NET Core Denial of Service Vulnerability'. This CVE ID is unique from CVE-2019-0980, CVE-2019-0981.

Affected products

Microsoft Corporation .NET Core: 1.0, 1.1, 2.1, 2.2
Microsoft .NET Framework: 2.0-sp2, 3.0-sp2, 3.5, 3.5.1, 4.5.2, 4.6 (+6)
Red Hat Enterprise Linux: 8.0
RedHat Enterprise Linux Eus: 8.1, 8.2, 8.4, 8.6
RedHat Enterprise Linux Server Aus: 8.2, 8.4, 8.6
RedHat Enterprise Linux Server Tus: 8.2, 8.4, 8.6
Microsoft Corporation .NET Core: 1, 1.1, 2.1, 2.2
Microsoft .NET Framework 2.0: Service Pack 2 on Windows Server 2008 for Itanium-Based Systems Service Pack 2, Service Pack 2 on Windows Server 2008 for 32-bit Systems Service Pack 2, Service Pack 2 on Windows Server 2008 for x64-based Systems Service Pack 2
Microsoft .NET Framework 3.0: Service Pack 2 on Windows Server 2008 for Itanium-Based Systems Service Pack 2, Service Pack 2 on Windows Server 2008 for 32-bit Systems Service Pack 2, Service Pack 2 on Windows Server 2008 for x64-based Systems Service Pack 2
Microsoft .NET Framework 3.5: Windows Server 2012, Windows Server 2012 (Server Core installation), Windows 8.1 for 32-bit systems, Windows 8.1 for x64-based systems, Windows Server 2012 R2, Windows Server 2012 R2 (Server Core installation) (+19)
Microsoft .NET Framework 3.5.1: Windows 7 for 32-bit Systems Service Pack 1, Windows 7 for x64-based Systems Service Pack 1, Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation), Windows Server 2008 R2 for Itanium-Based Systems Service Pack 1, Windows Server 2008 R2 for x64-based Systems Service Pack 1
Microsoft .NET Framework 3.5 on Windows 10 Version 1903 for 32-bit Systems: all versions
Microsoft .NET Framework 3.5 on Windows 10 Version 1903 for x64-based Systems: all versions
Microsoft .NET Framework 3.5 on Windows Server, version 1903 (Server Core installation): all versions
Microsoft .NET Framework 4.5.2: Windows 7 for 32-bit Systems Service Pack 1, Windows 7 for x64-based Systems Service Pack 1, Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation), Windows Server 2008 R2 for x64-based Systems Service Pack 1, Windows Server 2012, Windows Server 2012 (Server Core installation) (+7)
Microsoft .NET Framework 4.6: Windows Server 2008 for 32-bit Systems Service Pack 2, Windows Server 2008 for x64-based Systems Service Pack 2
Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2: Windows Server 2016, Windows Server 2016 (Server Core installation)
Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2: Windows 7 for 32-bit Systems Service Pack 1, Windows 7 for x64-based Systems Service Pack 1, Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation), Windows Server 2008 R2 for x64-based Systems Service Pack 1, Windows Server 2012, Windows Server 2012 (Server Core installation) (+5)
Microsoft .NET Framework 4.7.2: Windows 10 Version 1803 for 32-bit Systems, Windows 10 Version 1803 for x64-based Systems, Windows Server, version 1803 (Server Core Installation), Windows 10 Version 1803 for ARM64-based Systems, Windows Server 2019, Windows Server 2019 (Server Core installation)
Microsoft .NET Framework 4.8 on Windows 10 Version 1607 for 32-bit Systems: all versions
Microsoft .NET Framework 4.8 on Windows 10 Version 1607 for x64-based Systems: all versions
Microsoft .NET Framework 4.8 on Windows 10 Version 1703 for 32-bit Systems: all versions
Microsoft .NET Framework 4.8 on Windows 10 Version 1703 for x64-based Systems: all versions
Microsoft .NET Framework 4.8 on Windows 10 Version 1709 for 32-bit Systems: all versions
Microsoft .NET Framework 4.8 on Windows 10 Version 1709 for x64-based Systems: all versions
Microsoft .NET Framework 4.8 on Windows 10 Version 1803 for 32-bit Systems: all versions
Microsoft .NET Framework 4.8 on Windows 10 Version 1803 for x64-based Systems: all versions
Microsoft .NET Framework 4.8 on Windows 10 Version 1809 for 32-bit Systems: all versions
Microsoft .NET Framework 4.8 on Windows 10 Version 1809 for x64-based Systems: all versions
Microsoft .NET Framework 4.8 on Windows 10 Version 1903 for 32-bit Systems: all versions

References

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