Analysis of active exploitation of SolarWinds Web Help Desk

The Microsoft Defender Research Team observed a multi‑stage intrusion where threat actors exploited internet‑exposed SolarWinds Web Help Desk WHD instances to get an initial foothold and then laterally moved towards other high-value assets within the organization. However, we have not yet confirm...

New Clickfix variant ‘CrashFix’ deploying Python Remote Access Trojan

In January 2026, Microsoft Defender Experts identified a new evolution in the ongoing ClickFix campaign. This updated tactic deliberately crashes victims’ browsers and then attempts to lure users into executing malicious commands under the pretext of restoring normal functionality. This variant...

New Clickfix variant ‘CrashFix’ deploying Python Remote Access Trojan

In January 2026, Microsoft Defender Experts identified a new evolution in the ongoing ClickFix campaign. This updated tactic deliberately crashes victims’ browsers and then attempts to lure users into executing malicious commands under the pretext of restoring normal functionality. This variant...

The security implementation gap: Why Microsoft is supporting Operation Winter SHIELD

Every conversation I have with information security leaders tends to land in the same place. People understand what matters. They know the frameworks, the controls, and the guidance. They can explain why identity security, patching, and access control are critical. And yet incidents keep happenin...

The security implementation gap: Why Microsoft is supporting Operation Winter SHIELD

Every conversation I have with information security leaders tends to land in the same place. People understand what matters. They know the frameworks, the controls, and the guidance. They can explain why identity security, patching, and access control are critical. And yet incidents keep happenin...

Detecting backdoored language models at scale

Today, we are releasing new research on detecting backdoors in open-weight language models. Our research highlights several key properties of language model backdoors, laying the groundwork for a practical scanner designed to detect backdoored models at scale and improve overall trust in AI...

Detecting backdoored language models at scale

Today, we are releasing new research on detecting backdoors in open-weight language models. Our research highlights several key properties of language model backdoors, laying the groundwork for a practical scanner designed to detect backdoored models at scale and improve overall trust in AI...

Microsoft SDL: Evolving security practices for an AI-powered world

As AI reshapes the world, organizations encounter unprecedented risks, and security leaders take on new responsibilities. Microsoft’s Secure Development Lifecycle SDL is expanding to address AI-specific security concerns in addition to the traditional software security areas that it has...

Microsoft SDL: Evolving security practices for an AI-powered world

As AI reshapes the world, organizations encounter unprecedented risks, and security leaders take on new responsibilities. Microsoft’s Secure Development Lifecycle SDL is expanding to address AI-specific security concerns in addition to the traditional software security areas that it has...

Infostealers without borders: macOS, Python stealers, and platform abuse

Infostealer threats are rapidly expanding beyond traditional Windows-focused campaigns, increasingly targeting macOS environments, leveraging cross-platform languages such as Python, and abusing trusted platforms and utilities to silently deliver credential-stealing malware at scale. Since late...

Infostealers without borders: macOS, Python stealers, and platform abuse

Infostealer threats are rapidly expanding beyond traditional Windows-focused campaigns, increasingly targeting macOS environments, leveraging cross-platform languages such as Python, and abusing trusted platforms and utilities to silently deliver credential-stealing malware at scale. Since late...

Case study: Securing AI application supply chains

The rapid adoption of AI applications, including agents, orchestrators, and autonomous workflows, represents a significant shift in how software systems are built and operated. Unlike traditional applications, these systems are active participants in execution. They make decisions, invoke tools,...

Case study: Securing AI application supply chains

The rapid adoption of AI applications, including agents, orchestrators, and autonomous workflows, represents a significant shift in how software systems are built and operated. Unlike traditional applications, these systems are active participants in execution. They make decisions, invoke tools,...

Turning threat reports into detection insights with AI

Security teams routinely need to transform unstructured threat knowledge, such as incident narratives, red team breach-path writeups, threat actor profiles, and public reports into concrete defensive action. The early stages of that work are often the slowest. These include extracting tactics,...

Turning threat reports into detection insights with AI

Security teams routinely need to transform unstructured threat knowledge, such as incident narratives, red team breach-path writeups, threat actor profiles, and public reports into concrete defensive action. The early stages of that work are often the slowest. These include extracting tactics,...

New Microsoft Data Security Index report explores secure AI adoption to protect sensitive data

Generative AI and agentic AI are redefining how organizations innovate and operate, unlocking new levels of productivity, creativity and collaboration across industry teams. From accelerating content creation to streamlining workflows, AI offers transformative benefits that empower organizations ...

New Microsoft Data Security Index report explores secure AI adoption to protect sensitive data

Generative AI and agentic AI are redefining how organizations innovate and operate, unlocking new levels of productivity, creativity and collaboration across industry teams. From accelerating content creation to streamlining workflows, AI offers transformative benefits that empower organizations ...

Microsoft announces the 2026 Security Excellence Awards winners

In today’s fast‑moving digital arena, security isn’t a solo act—it’s a team sport. Every day, defenders across the globe suit up, strategize, and work shoulder‑to‑shoulder to protect organizations and communities from an ever‑evolving field of cyberthreats. That shared spirit of collaboration is...

Security strategies for safeguarding governmental data

The Deputy CISO blog series is where Microsoft Deputy Chief Information Security Officers CISOs share their thoughts on what is most important in their respective domains. In this series, you will get practical advice, tactics to start and stop deploying, forward-looking commentary on where the...

Security strategies for safeguarding governmental data

The Deputy CISO blog series is where Microsoft Deputy Chief Information Security Officers CISOs share their thoughts on what is most important in their respective domains. In this series, you will get practical advice, tactics to start and stop deploying, forward-looking commentary on where the...

From runtime risk to real‑time defense: Securing AI agents

AI agents, whether developed in Microsoft Copilot Studio or on alternative platforms, are becoming a powerful means for organizations to create custom solutions designed to enhance productivity and automate organizational processes by seamlessly integrating with internal data and systems. From a...

Microsoft Security success stories: Why integrated security is the foundation of AI transformation

AI is transforming how organizations operate and how they approach security. In this new era of agentic AI, every interaction, digital or human, must be built on trust. As businesses modernize, they’re not just adopting AI tools, they're rearchitecting their digital foundations. And that means...

Microsoft Security success stories: Why integrated security is the foundation of AI transformation

AI is transforming how organizations operate and how they approach security. In this new era of agentic AI, every interaction, digital or human, must be built on trust. As businesses modernize, they’re not just adopting AI tools, they're rearchitecting their digital foundations. And that means...

Resurgence of a multi‑stage AiTM phishing and BEC campaign abusing SharePoint

Microsoft Defender Researchers uncovered a multi‑stage adversary‑in‑the‑middle AiTM phishing and business email compromise BEC campaign targeting multiple organizations in the energy sector, resulting in the compromise of various user accounts. The campaign abused SharePoint file‑sharing services...

Resurgence of a multi‑stage AiTM phishing and BEC campaign abusing SharePoint

Microsoft Defender Researchers uncovered a multi‑stage adversary‑in‑the‑middle AiTM phishing and business email compromise BEC campaign targeting multiple organizations in the energy sector, resulting in the compromise of various user accounts. The campaign abused SharePoint file‑sharing services...

A new era of agents, a new era of posture

The rise of AI Agents marks one of the most exciting shifts in technology today. Unlike traditional applications or cloud resources, these agents are not passive components- they reason, make decisions, invoke tools, and interact with other agents and systems on behalf of users. This autonomy...

A new era of agents, a new era of posture

The rise of AI Agents marks one of the most exciting shifts in technology today. Unlike traditional applications or cloud resources, these agents are not passive components- they reason, make decisions, invoke tools, and interact with other agents and systems on behalf of users. This autonomy...

Four priorities for AI-powered identity and network access security in 2026

No doubt, your organization has been hard at work over the past several years implementing industry best practices, including a Zero Trust architecture. But even so, the cybersecurity race only continues to intensify. AI has quickly become a powerful tool misused by threat actors, who use it to...

Four priorities for AI-powered identity and network access security in 2026

No doubt, your organization has been hard at work over the past several years implementing industry best practices, including a Zero Trust architecture. But even so, the cybersecurity race only continues to intensify. AI has quickly become a powerful tool misused by threat actors, who use it to...

Microsoft named a Leader in IDC MarketScape for Unified AI Governance Platforms

As organizations rapidly embrace generative and agentic AI, ensuring robust, unified governance has never been more critical. That’s why Microsoft is honored to be named a Leader in the2025-2026 IDC MarketScape for Worldwide Unified AI Governance Platforms Vendor Assessment US53514825, December...

Microsoft named a Leader in IDC MarketScape for Unified AI Governance Platforms

As organizations rapidly embrace generative and agentic AI, ensuring robust, unified governance has never been more critical. That’s why Microsoft is honored to be named a Leader in the2025-2026 IDC MarketScape for Worldwide Unified AI Governance Platforms Vendor Assessment US53514825, December...

Inside RedVDS: How a single virtual desktop provider fueled worldwide cybercriminal operations

Over the past year, Microsoft Threat Intelligence observed the proliferation of RedVDS, a virtual dedicated server VDS provider used by multiple financially motivated threat actors to commit business email compromise BEC, mass phishing, account takeover, and financial fraud. Microsoft’s...

Inside RedVDS: How a single virtual desktop provider fueled worldwide cybercriminal operations

Over the past year, Microsoft Threat Intelligence observed the proliferation of RedVDS, a virtual dedicated server VDS provider used by multiple financially motivated threat actors to commit business email compromise BEC, mass phishing, account takeover, and financial fraud. Microsoft’s...

How Microsoft builds privacy and security to work hand-in-hand

The Deputy CISO blog series is where Microsoft Deputy Chief Information Security Officers CISOs share their thoughts on what is most important in their respective domains. In this series, you will get practical advice, tactics to start and stop deploying, forward-looking commentary on where the...

How Microsoft builds privacy and security to work hand-in-hand

The Deputy CISO blog series is where Microsoft Deputy Chief Information Security Officers CISOs share their thoughts on what is most important in their respective domains. In this series, you will get practical advice, tactics to start and stop deploying, forward-looking commentary on where the...

Explore the latest Microsoft Incident Response proactive services for enhanced resilience

As cyberthreats become faster, harder to detect, and more sophisticated, organizations must focus on building resilience—strengthening their ability to prevent, withstand, and recover from cybersecurity incidents. Resilience can mean the difference between containing an incident with minimal...

Explore the latest Microsoft Incident Response proactive services for enhanced resilience

As cyberthreats become faster, harder to detect, and more sophisticated, organizations must focus on building resilience—strengthening their ability to prevent, withstand, and recover from cybersecurity incidents. Resilience can mean the difference between containing an incident with minimal...

Phishing actors exploit complex routing and misconfigurations to spoof domains

Phishing actors are exploiting complex routing scenarios and misconfigured spoof protections to effectively spoof organizations’ domains and deliver phishing emails that appear, superficially, to have been sent internally. Threat actors have leveraged this vector to deliver a wide variety of...

Phishing actors exploit complex routing and misconfigurations to spoof domains

Phishing actors are exploiting complex routing scenarios and misconfigured spoof protections to effectively spoof organizations’ domains and deliver phishing emails that appear, superficially, to have been sent internally. Threat actors have leveraged this vector to deliver a wide variety of...

Introducing the Microsoft Defender Experts Suite: Elevate your security with expert-led services

Security teams are being pushed to their limits as AI‑powered cyberattacks grow in speed, scale, and sophistication—and only 14% of organizations surveyed by the World Economic Forum report they feel confident they have the right people and skills needed to meet their cybersecurity objectives.1 A...

New Microsoft e-book: 3 reasons point solutions are holding you back

While patchwork tools slow defenders down and impact visibility into potential cyberthreats, they’re an unfortunate reality for many organizations. As digital risk accelerates and attack surfaces multiply, security leaders are doing their best to stitch together point solutions while trying to...

New Microsoft e-book: 3 reasons point solutions are holding you back

While patchwork tools slow defenders down and impact visibility into potential cyberthreats, they’re an unfortunate reality for many organizations. As digital risk accelerates and attack surfaces multiply, security leaders are doing their best to stitch together point solutions while trying to...

Access Fabric: A modern approach to identity and network access

Today, most organizations use multiple identity systems and multiple network access solutions from multiple vendors. This happens, either intentionally or organically, when different areas of a company choose different tools, creating a fragmented environment that leaves weaknesses that...

Access Fabric: A modern approach to identity and network access

Today, most organizations use multiple identity systems and multiple network access solutions from multiple vendors. This happens, either intentionally or organically, when different areas of a company choose different tools, creating a fragmented environment that leaves weaknesses that...

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, Next.js, and related frameworks. With a CVSS score of 10.0, this vulnerability could all...

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, Next.js, and related frameworks. With a CVSS score of 10.0, this vulnerability could all...

Microsoft named an overall leader in KuppingerCole Leadership Compass for Generative AI Defense

Today, we are proud to share that Microsoft has been recognized as an overall leader in the KuppingerCole Leadership Compass for Generative AI Defense GAD, an independent report from a leading European analyst firm. This recognition reinforces the work we’ve been doing to deliver enterprise-ready...

Microsoft named an overall leader in KuppingerCole Leadership Compass for Generative AI Defense

Today, we are proud to share that Microsoft has been recognized as an overall leader in the KuppingerCole Leadership Compass for Generative AI Defense GAD, an independent report from a leading European analyst firm. This recognition reinforces the work we’ve been doing to deliver enterprise-ready...

Imposter for hire: How fake people can gain very real access

In the latest edition of our Cyberattack Series, we dive into a real-world case of fake employees. Cybercriminals are no longer just breaking into networks—they’re gaining access by posing as legitimate employees. This form of cyberattack involves operatives posing as legitimate remote hires,...

Imposter for hire: How fake people can gain very real access

In the latest edition of our Cyberattack Series, we dive into a real-world case of fake employees. Cybercriminals are no longer just breaking into networks—they’re gaining access by posing as legitimate employees. This form of cyberattack involves operatives posing as legitimate remote hires,...