From .NET Blog · 40 stories
Adobe Patches Critical ColdFusion and Campaign Classic Vulnerabilities Amid Exploits
Adobe released patches for critical vulnerabilities in ColdFusion and Campaign Classic, some of which are actively being exploited for remote code execution. These security flaws, including CVE-2026-48282, have CVSS scores of 10.0, marking them as maximum severity. The urgency of these updates highlights the importance of securing systems to prevent unauthorized access and potential attacks.
Strategic Frameworks and Systems Vital for Successful AI Integration in Enterprises
AI's integration in enterprises is moving beyond model development to focus on creating robust systems for execution and governance. This shift highlights the importance of developing adaptable frameworks to support AI's role across various functions such as finance, HR, and operations. It reflects a broader industry trend where the focus is on building the necessary infrastructure to ensure AI's ongoing, safe, and productive incorporation into real-world workflows, addressing the current challenges and limitations.
Meta Introduces Hybrid Asset Classification for Privacy-Aware Infrastructure
Meta has unveiled a hybrid asset classification strategy using large language models (LLMs) to handle ambiguous data in privacy-aware infrastructure while maintaining deterministic rules for enforcement. This method addresses the complexities of AI-native products with varied data inputs, ensuring compliance and effective data governance. It is a response to the challenges posed by the increasing speed and scale of AI innovations, and the approach aims to better manage privacy controls for evolving AI products.
GitHub Copilot Enhances Efficiency with Improved Context Handling and Model Selection
GitHub Copilot has introduced improvements in context handling and model routing for Visual Studio Code, boosting productivity without user involvement. The updates enhance prompt caching and enable automatic model selection aligned with tasks. This development could impact software development workflows by optimizing resource use and maintaining quality in longer coding sessions.
DeepSeek Launches Open-Source AI Agent Harness and Updates Flagship Model
DeepSeek has released DeepSeek Harness (dsh) in developer preview, an open-source AI agent runtime built with a plugin-based architecture under an MIT license. Concurrently, the company launched DeepSeek-V4-Pro, an updated flagship AI model optimized for agentic workloads, which is now available via API with new peak and off-peak pricing.
Model Context Protocol (MCP) 2026-07-28 Specification Released, Adopting Stateless Core
The Model Context Protocol (MCP) has released its 2026-07-28 specification, transitioning from a bidirectional stateful protocol to a request/response stateless core. This update, the largest revision since its launch, aims to improve reliability and scalability for MCP servers, addressing a highly requested developer feature. Major SDKs, including TypeScript, Python, and C#, have been updated to support the new specification.
Microsoft introduces dotnetup, a .NET toolchain manager for macOS and Linux
Microsoft has released a public preview of dotnetup, a new toolchain manager for .NET SDKs and runtimes on macOS and Linux. This tool aims to simplify installation, management, and updates by operating within user accounts, avoiding system-level permissions and conflicts.
.NET 11 Release Candidate 2 is Available with Go-Live Support
.NET 11 Release Candidate 2 is now available, offering go-live support for production applications. This release introduces updates across libraries, runtime, SDK, F#, ASP.NET Core, .NET MAUI, and Windows Forms, and is supported in Visual Studio 2026 Insiders and Visual Studio Code with C# Dev Kit.
.NET 11 Preview 7 Released with Updates Across Libraries, Runtime, SDK, and Frameworks
Microsoft has released .NET 11 Preview 7, introducing improvements across various components including libraries, the .NET Runtime, SDK, C#, ASP.NET Core, .NET MAUI, Entity Framework Core, F#, and Windows Forms. This preview provides developers with new features and enhancements for application development across different platforms.
.NET 11 Preview 6 Released with New Optimizations and Features
.NET 11 Preview 6 has been released, offering enhancements across several aspects like the runtime, SDK, libraries, ASP.NET Core, and .NET MAUI. New features include asynchronous validation, improved JSON serialization, and performance optimizations for future development iterations. The preview aims to improve development efficiency and capability, reflecting significant advances since the prior preview release.
.NET Conf 2026 to Launch .NET 11 and Feature Microsoft & Community Sessions
.NET Conf 2026, a free four-day virtual conference, will take place from November 10-13, featuring the official launch of .NET 11. The event includes two days of sessions from Microsoft product teams and two days of community-led talks, covering new features in .NET 11, C#, ASP.NET Core, Blazor, .NET MAUI, and AI integration.
Infragistics Contributes 50+ Open-Source Blazor Controls and .NET 11 Analyzers
Infragistics has open-sourced over 50 Blazor UI controls and is contributing directly to the Blazor framework with new analyzers for .NET 11. This collaboration provides free components for developers and improves Blazor's core tooling for all users.
.NET MAUI Apps Require UI Scene Lifecycle for Xcode 27 Compatibility
.NET MAUI applications built with Xcode 27 and running on iOS 27 will crash unless they adopt UIKit's scene lifecycle. This change is a compatibility requirement for all iOS apps built with the new SDK, not a bug in .NET MAUI itself.
C# Dev Kit 11.0 Rearchitected for Performance and Memory Improvements
C# Dev Kit 11.0 has been rearchitected to improve performance and memory usage, aligning its version with .NET 11. This update reduces load times for large solutions by using project caches and consolidating processes, allowing developers to begin work faster.
MSTest 4.5 and Microsoft.Testing.Platform 2.5 Enable UI Testing for UWP and WinUI 3 Apps
MSTest 4.5 and Microsoft.Testing.Platform 2.5 now support UI-thread testing for UWP and WinUI 3 applications, allowing test code to run with UI-thread access. This update simplifies testing for various UWP and WinUI 3 app models by handling app launch paths and enabling a sidecar controller for test execution.
.NET SDK for AG-UI Protocol Released, Standardizing Agent-User Interaction
A .NET SDK for the AG-UI (Agent-User Interaction) Protocol has been released, allowing .NET services to directly communicate using the protocol. This SDK standardizes how AI agents interact with user-facing applications by providing a common event-streaming format, reducing boilerplate for developers.
Microsoft to update NuGet package author-signing certificate by September 23, 2026
Microsoft will transition to a new author-signing certificate for its NuGet packages starting September 23, 2026. Users who validate Microsoft-signed packages via NuGet client policies or the dotnet nuget verify command must update their configurations to include the new certificate fingerprint to avoid disruptions.
.NET 11 Release Candidate 1 is Available with Go-Live Support
.NET 11 Release Candidate 1 has been released, offering go-live support for production applications. This version includes updates across libraries, runtime, SDK, MSBuild, NuGet, C#, F#, ASP.NET Core, .NET MAUI, and Windows Forms, and is supported in Visual Studio 2026 Insiders and Visual Studio Code with C# Dev Kit.
.NET and .NET Framework receive September 2026 servicing releases with security fixes
Microsoft released the September 2026 servicing updates for .NET and .NET Framework, which include security and non-security fixes. These updates address various CVEs and refresh components like ASP.NET Core, Entity Framework Core, and Runtime to new versions. This matters to developers using these frameworks as it ensures their applications remain secure and stable.
MSTest 4.4 Adds Support for Native AOT Test Execution
MSTest version 4.4 now supports publishing and running test projects as Native AOT executables, allowing developers to test applications in a configuration closer to their final deployment. This update addresses discrepancies that can arise when Native AOT's ahead-of-time compilation and code trimming alter application behavior compared to standard managed test runs.
C# 15 Preview Introduces Union Types, Closed Hierarchies, and Updated Unsafe Model
C# 15, set to release with .NET 11 in November, is now available in .NET 11 preview 7, introducing features like union types, closed hierarchies, and an updated unsafe model. These additions enhance type system expressiveness and control over inheritance, impacting how developers define and manage data structures.
Microsoft.Extensions.AI introduces new primitives for AI model routing and failover
Microsoft.Extensions.AI has released new experimental primitives for routing and failover in AI applications, addressing cost, uptime, and latency concerns. These primitives allow developers to route requests based on content or implement failover strategies for AI models and providers.
NuGet.org to Limit API Key Lifetimes to 30 Days Starting August 2026
NuGet.org will restrict new API keys to a 30-day maximum duration starting August 17, 2026, and all existing keys will expire by November 1, 2026. This change aims to reduce the risk of supply chain attacks by limiting the window of opportunity for attackers if credentials are compromised.
Open-source code-testing-generator agent released for automated unit test creation
A new open-source, polyglot agent named code-testing-generator has been released to automate the generation of unit tests. This agent learns from a repository, plans test creation, writes tests, and validates their functionality, including integration into the project's build system.
MSBuild Binlog Analyzer for VS Code integrates Copilot for build log analysis
Microsoft released the MSBuild Binlog Analyzer for VS Code, a new extension that integrates GitHub Copilot Chat to analyze MSBuild binary logs directly within the editor. This tool helps developers diagnose build failures, identify performance bottlenecks, and compare build changes without leaving their development environment.
GitHub Copilot App Introduces Interactive .NET Modernization Tools
GitHub Copilot app has introduced an interactive upgrade canvas to assist in modernizing .NET applications, providing real-time workflow management. Additionally, the new .NET Modernization for Beginners course offers hands-on guidance to help developers upgrade legacy ASP.NET applications. These changes simplify the modernization process and offer educational support for developers navigating these upgrades.
June and July 2026 .NET Updates Address Security Vulnerabilities
The .NET platform received updates in June and July 2026, focusing on addressing security vulnerabilities. While June's update included fixes for existing issues in .NET, July's update also introduced new non-security enhancements for the .NET Framework.
CoreCLR Becomes Default Runtime for .NET MAUI Mobile Apps in Preview 6
CoreCLR is now the only runtime for .NET MAUI mobile apps in Preview 6, replacing Mono. This transition enhances performance consistency across iOS, Android, and Mac Catalyst while laying the groundwork for future developments in .NET 11.
Microsoft's Binlog MCP Server Enhances Build Diagnostics via AI Integration
Microsoft has launched the Binlog MCP Server, allowing AI tools to analyze MSBuild logs for build diagnostics. This integration supports automated diagnostics in GitHub Actions, improving error tracing and performance analysis. It simplifies build failure analysis through natural language queries, benefiting developers by providing root cause explanations faster.
.NET 8 and .NET 9 will reach end of support on November 10, 2026
.NET 8 and .NET 9 will no longer receive updates or support after November 10, 2026. Microsoft recommends upgrading to .NET 10 for continued security updates and support, as both versions will leave users exposed to vulnerabilities without patches.
SkiaSharp 4.0 Released with Enhanced Features and Stability
SkiaSharp 4.148.0 is now released as the first stable version of v4, enhancing cross-platform 2D graphics in .NET. This update includes improved performance, new capabilities like animated WebP encoding, and a cleaner API, making it a significant upgrade for developers using this graphics library.
WinApp CLI Simplifies Package Identity for .NET Apps on Windows
The WinApp CLI simplifies package identity for Windows apps, facilitating integration with Windows features. It allows .NET developers to easily test apps with package identity and package applications as MSIX.
.NET Day on Agentic Modernization Livestream Set for June 2026
Microsoft Reactor will host .NET Day on June 16, 2026, focusing on modernizing .NET applications. The event aims to address cloud migration and legacy maintenance while incorporating AI-driven capabilities.
.NET Highlights from Microsoft Build 2026 Focus on AI Integration
.NET 11 showcased significant advancements including union types in C# and AI integration across applications. The sessions emphasized new features designed to enhance developer productivity and create intelligent applications in an AI-driven landscape.
Microsoft Opens 2026 .NET Developer Survey to Gather Feedback
Microsoft has launched the 2026 .NET Developer Survey to collect feedback from developers on their experiences with the .NET platform. The survey aims to inform the .NET team's future investment decisions and understand common challenges faced by users.
NuGet Packages Can Now Distribute AI Agent Skills
AI agent skills, previously distributed via Git repositories, can now be delivered through NuGet packages. This new distribution method allows for just-in-time skill delivery, ensuring agents have access to the latest capabilities ahead of model training.
.NET and .NET Framework receive October 2026 servicing updates
.NET and .NET Framework received their October 2026 servicing updates, which include security and non-security fixes. These updates address vulnerabilities and provide general improvements for supported versions of both platforms.
.NET Conf 2026 Community Days Call for Presenters Now Open
The call for presenters for .NET Conf 2026 Community Days is open from September 8 to October 6, 2026. This year, the community will fully manage the Community Days, including session selection and event production, marking a shift from previous years where Microsoft's team led these aspects.
.NET and .NET Framework receive August 2026 servicing updates with security fixes
Microsoft released servicing updates for .NET and .NET Framework in August 2026, including security and non-security fixes. These updates address specific CVEs and provide refreshed versions for ASP.NET Core, Entity Framework Core, and Runtime components. The updates are important for maintaining the security and stability of applications built on these platforms.
Microsoft.Testing.Platform improves test reporting for CI/CD pipelines
Microsoft.Testing.Platform (MTP) has updated its reporting features to provide inline test failure annotations in GitHub Actions and Azure DevOps, aiming to streamline the debugging process for developers. These updates, available in MTP 2.3.0 and later, integrate test results directly into developer workflows, reducing the need to search logs or download artifacts.