Resource exhaustion in Microsoft products - CVE-2026-45591

Vulnerability identifier: #VU134477

CSH Severity: Medium

CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-45591

CWE-ID: CWE-400

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to application does not properly control consumption of internal resources in ASP.NET Core. A remote attacker can trigger resource exhaustion and perform a denial of service (DoS) attack.

.NET for Linux
.NET for macOS
ASP.NET Core
.NET
Microsoft .NET Framework
Red Hat Enterprise Linux for IBM z Systems
Red Hat CodeReady Linux Builder for ARM 64
Red Hat CodeReady Linux Builder for Power, little endian
Red Hat CodeReady Linux Builder for x86_64
Red Hat Enterprise Linux for ARM 64
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for x86_64
Red Hat CodeReady Linux Builder for IBM z Systems
Red Hat Enterprise Linux Server - AUS
Red Hat Enterprise Linux for x86_64 - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support
Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support
Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support
Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support
Ubuntu
Fedora
Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions
dotnet10 (Ubuntu package)
dotnet8.0 (Red Hat package)
dotnet8.0
dotnet9.0 (Red Hat package)
dotnet9.0
dotnet10.0

Install updates from vendor's website.

.NET for Linux - addressed in versions 8.0.28, 9.0.17
.NET for macOS - addressed in versions 8.0.28, 9.0.17
ASP.NET Core - addressed in versions 8.0.28, 9.0.17
.NET - addressed in versions 8.0.28, 9.0.17
Microsoft .NET Framework - update to 10.0.9
dotnet10 (Ubuntu package) - addressed in versions 8.0.28-0ubuntu1~22.04.1, 8.0.28-0ubuntu1~24.04.1, 8.0.28-0ubuntu1~25.10.1, 8.0.128-0ubuntu1~22.04.1, 8.0.128-0ubuntu1~24.04.1, 8.0.128-0ubuntu1~25.10.1, 8.0.128-8.0.28-0ubuntu1~22.04.1, 8.0.128-8.0.28-0ubuntu1~24.04.1, 8.0.128-8.0.28-0ubuntu1~25.10.1, 9.0.17-0ubuntu1~25.10.1, 9.0.118-0ubuntu1~25.10.1, 9.0.118-9.0.17-0ubuntu1~25.10.1, 10.0.9-0ubuntu1~24.04.1, 10.0.9-0ubuntu1~25.10.1, 10.0.9-0ubuntu1~26.04.1, 10.0.109-0ubuntu1~24.04.1, 10.0.109-0ubuntu1~25.10.1, 10.0.109-0ubuntu1~26.04.1, 10.0.109-10.0.9-0ubuntu1~24.04.1, 10.0.109-10.0.9-0ubuntu1~25.10.1, 10.0.109-10.0.9-0ubuntu1~26.04.1
dotnet8.0 (Red Hat package) - addressed in versions 8.0.128-1.el8_10, 8.0.128-1.el9_6, 8.0.128-1.el10_0, 8.0.128-1.el10_2
dotnet8.0 - addressed in versions 8.0.128-1.fc43, 8.0.128-1.fc44
dotnet9.0 (Red Hat package) - addressed in versions 9.0.118-1.el8_10, 9.0.118-1.el10_0
dotnet9.0 - addressed in versions 9.0.118-1.fc43, 9.0.118-1.fc44
dotnet10.0 - update to 10.0.109-1.fc43

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45591

• Denial of service in Microsoft ASP.NET Core
• Red Hat Enterprise Linux 8 update for .NET 8.0
• Red Hat Enterprise Linux 10 update for .NET 8.0
• Red Hat Enterprise Linux 8 update for .NET 9.0
• Ubuntu update for dotnet10
• Fedora 43 update for dotnet10.0
• Fedora 43 update for dotnet9.0
• Fedora 44 update for dotnet9.0
• Fedora 43 update for dotnet8.0
• Fedora 44 update for dotnet8.0
• Red Hat Enterprise Linux 10 update for .NET 8.0
• Red Hat Enterprise Linux 10 update for .NET 9.0
• Red Hat Enterprise Linux 9 update for .NET 8.0