Microsoft Defender email security benchmarking: Key insights from one year of data

Collection of Microsoft Security Blog posts (June 2026) covering real-world threat research and defensive guidance. Key items: Microsoft Defender email security benchmarking results; ASSERT (open-source framework) for converting specs into executable AI evaluations; a telemetry-driven playbook for reconstructing AI activity in Microsoft 365 Copilot and Azure AI; analysis of threat actors using AI branding as social-engineering lures; discovery of a prompt-injection pathway in the Claude Code GitHub Action that could expose workflow secrets (responsible disclosure and Anthropic mitigation); an