Microsoft Security Blog
Your source for the latest in cybersecurity
Microsoft Security success stories: Why integrated security is the foundation of AI transformation
Discover how Ford, Icertis, and TriNet modernized security with Microsoft—embedding Zero Trust, automating defenses, and enabling secure AI innovation at scale.
Introducing the Microsoft Defender Experts Suite: Elevate your security with expert-led services
Announcing Microsoft Defender Experts Suite, a integrated set of expert-led services that helps security teams keep pace with modern cyberattacks.
Threat intelligence
-
Inside RedVDS: How a single virtual desktop provider fueled worldwide cybercriminal operations
Microsoft’s investigation into RedVDS services and infrastructure uncovered a global network of disparate cybercriminals purchasing and using to target multiple sectors. -
Phishing actors exploit complex routing and misconfigurations to spoof domains
Threat actors are exploiting complex routing scenarios and misconfigured spoof protections to send spoofed phishing emails, crafted to appear as internally sent messages. -
Defending against the CVE-2025-55182 (React2Shell) vulnerability in React Server Components
CVE-2025-55182 (also referred to as React2Shell and includes CVE-2025-66478, which was merged into it) is a critical pre-authentication remote code execution (RCE) vulnerability affecting React Server Components and related frameworks.
Stay ahead of threats
Get expert insights, threat intelligence, and the latest cybersecurity reports from Security Insider.
AI and machine learning
-
Microsoft Security success stories: Why integrated security is the foundation of AI transformation
Discover how Ford, Icertis, and TriNet modernized security with Microsoft—embedding Zero Trust, automating defenses, and enabling secure AI innovation at scale. -
Four priorities for AI-powered identity and network access security in 2026
Discover four key identity and access priorities for the new year to strengthen your organization’s identity security baseline. -
Microsoft named a Leader in IDC MarketScape for Unified AI Governance Platforms
Microsoft is honored to be named a Leader in the 2025–2026 IDC MarketScape for Unified AI Governance Platforms, highlighting our commitment to making AI innovation safe, responsible, and enterprise-ready.
Modernize your security operations center
Confidently secure your multicloud, multiplatform environment with Microsoft Sentinel – a cloud-native security information and event management (SIEM) solution.
Latest posts
-
Microsoft Security success stories: Why integrated security is the foundation of AI transformation
Discover how Ford, Icertis, and TriNet modernized security with Microsoft—embedding Zero Trust, automating defenses, and enabling secure AI innovation at scale. -
Resurgence of a multi‑stage AiTM phishing and BEC campaign abusing SharePoint
Microsoft Defender Researchers uncovered a multi‑stage AiTM phishing and business email compromise (BEC) campaign targeting multiple organizations in the energy sector. -
A new era of agents, a new era of posture
AI agents are transforming how organizations operate, but their autonomy also expands the attack surface. -
Four priorities for AI-powered identity and network access security in 2026
Discover four key identity and access priorities for the new year to strengthen your organization’s identity security baseline. -
Microsoft named a Leader in IDC MarketScape for Unified AI Governance Platforms
Microsoft is honored to be named a Leader in the 2025–2026 IDC MarketScape for Unified AI Governance Platforms, highlighting our commitment to making AI innovation safe, responsible, and enterprise-ready. -
Inside RedVDS: How a single virtual desktop provider fueled worldwide cybercriminal operations
Microsoft’s investigation into RedVDS services and infrastructure uncovered a global network of disparate cybercriminals purchasing and using to target multiple sectors.