Out-of-bounds read in Microsoft products - CVE-2025-21176

Vulnerability identifier: #VU102784

CSH Severity: High

CVSS v4: 8.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2025-21176

CWE-ID: CWE-125

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition in .NET, .NET Framework and Visual Studio. A remote attacker can create a specially crafted file, trick the victim into opening it, trigger an out-of-bounds read error and read contents of memory on the system, leading to arbitrary code execution.

Microsoft .NET Framework
.NET
Visual Studio
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 IBM z Systems
Red Hat Enterprise Linux for x86_64
Red Hat CodeReady Linux Builder for IBM z Systems
Ubuntu
Fedora
aspnetcore-runtime-8.0 (Ubuntu package)
dotnet-runtime-8.0 (Ubuntu package)
dotnet-host-8.0 (Ubuntu package)
dotnet-hostfxr-8.0 (Ubuntu package)
dotnet-sdk-8.0 (Ubuntu package)
dotnet8.0 (Red Hat package)
dotnet8.0
dotnet8 (Ubuntu package)
dotnet-runtime-9.0 (Ubuntu package)
dotnet-hostfxr-9.0 (Ubuntu package)
dotnet-host-9.0 (Ubuntu package)
aspnetcore-runtime-9.0 (Ubuntu package)
dotnet-sdk-9.0 (Ubuntu package)
dotnet9.0 (Red Hat package)
dotnet9.0
dotnet9 (Ubuntu package)

Install updates from vendor's website.

aspnetcore-runtime-8.0 (Ubuntu package) - addressed in versions 8.0.12-0ubuntu1~22.04.1, 8.0.12-0ubuntu1~24.04.1, 8.0.12-0ubuntu1~24.10.1
dotnet-runtime-8.0 (Ubuntu package) - addressed in versions 8.0.12-0ubuntu1~22.04.1, 8.0.12-0ubuntu1~24.04.1, 8.0.12-0ubuntu1~24.10.1
dotnet-host-8.0 (Ubuntu package) - addressed in versions 8.0.12-0ubuntu1~22.04.1, 8.0.12-0ubuntu1~24.04.1, 8.0.12-0ubuntu1~24.10.1
dotnet-hostfxr-8.0 (Ubuntu package) - addressed in versions 8.0.12-0ubuntu1~22.04.1, 8.0.12-0ubuntu1~24.04.1, 8.0.12-0ubuntu1~24.10.1
dotnet-sdk-8.0 (Ubuntu package) - addressed in versions 8.0.112-0ubuntu1~22.04.1, 8.0.112-0ubuntu1~24.04.1, 8.0.112-0ubuntu1~24.10.1
dotnet8.0 (Red Hat package) - addressed in versions 8.0.112-1.el8_10, 8.0.112-1.el9_4
dotnet8.0 - addressed in versions 8.0.112-1.fc40, 8.0.112-1.fc41
dotnet8 (Ubuntu package) - addressed in versions 8.0.112-8.0.12-0ubuntu1~22.04.1, 8.0.112-8.0.12-0ubuntu1~24.04.1, 8.0.112-8.0.12-0ubuntu1~24.10.1
dotnet-runtime-9.0 (Ubuntu package) - update to 9.0.1-0ubuntu1~24.10.1
dotnet-hostfxr-9.0 (Ubuntu package) - update to 9.0.1-0ubuntu1~24.10.1
dotnet-host-9.0 (Ubuntu package) - update to 9.0.1-0ubuntu1~24.10.1
aspnetcore-runtime-9.0 (Ubuntu package) - update to 9.0.1-0ubuntu1~24.10.1
dotnet-sdk-9.0 (Ubuntu package) - update to 9.0.102-0ubuntu1~24.10.1
dotnet9.0 (Red Hat package) - update to 9.0.102-1.el8_10
dotnet9.0 - addressed in versions 9.0.102-1.fc40, 9.0.102-1.fc41
dotnet9 (Ubuntu package) - update to 9.0.102-9.0.1-0ubuntu1~24.10.1

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2025-21176

• Remote code execution in Microsoft .NET, .NET Framework, and Visual Studio
• Ubuntu update for dotnet8
• Red Hat Enterprise Linux 8 update for .NET 8.0
• Red Hat Enterprise Linux 8 update for .NET 9.0
• Fedora 41 update for dotnet8.0
• Fedora 40 update for dotnet8.0
• Fedora 41 update for dotnet9.0
• Fedora 40 update for dotnet9.0
• Red Hat Enterprise Linux 9 update for .NET 8.0