AI-driven adaptive protection against human-operated ransomware

In human-operated ransomware attacks, threat actors use predictable methods to enter a device but eventually rely on hands-on-keyboard activities to move inside a network. To fortify our existing cloud-delivered automated protection against complex attacks like human-operated ransomware, we...

HTML smuggling surges: Highly evasive loader technique increasingly used in banking malware, targeted attacks

HTML smuggling, a highly evasive malware delivery technique that leverages legitimate HTML5 and JavaScript features, is increasingly used in email campaigns that deploy banking malware, remote access Trojans RATs, and other payloads related to targeted attacks. Notably, this technique was observe...

Microsoft achieves a Leader placement in Forrester Wave for XDR

We are excited to share that Microsoft has been named a Leader in The Forrester New Wave: Extended Detection and Response XDR, Q4, 2021,1 receiving one of the highest scores in the strategy category. Microsoft 365 Defender was rated as “differentiated” in seven criteria including detection,...

Improve your threat detection and response with Microsoft and Wortell

This blog post is part of the Microsoft Intelligent Security Association MISA guest blog series. Learn more about MISA. The way of working is changing rapidly. Many workloads are moving to the cloud and the pandemic accelerated organizations to provide infrastructure to aid employees working from...

Accelerate your adoption of SIEM using Azure Sentinel and a new offer from Microsoft

Take advantage of the efficiency benefits of Cloud-native SIEM using Azure Sentinel Today, security needs are evolving faster than ever—and the importance of being agile and cost-effective has never been clearer. Security teams need to get more done, faster, with less budget. On-premises security...

Afternoon Cyber Tea: Cybersecurity & IoT: New risks and how to minimize them

Recently, Microsoft announced our acquisition of CyberX, a comprehensive network-based security platform with continuous threat monitoring and analytics. This solution builds upon our commitment to provide a unified IoT security solution that addresses connected devices spread across both...

Developing an effective cyber strategy

The word strategy has its origins in the Roman Empire and was used to describe the leading of troops in battle. From a military perspective, strategy is a top-level plan designed to achieve one or more high-order goals. A clear strategy is especially important in times of uncertainty as it provid...

Securing our future: July 2026 progress report on Microsoft’s Secure Future Initiative

Security is never finished. That conviction is where the Secure Future Initiative SFI started two years ago and continues to guide us today. AI is reshaping cybersecurity. Cyberattackers can discover vulnerabilities, chain attack paths, and scale exploitation faster than manual approaches allow...

What’s new in Microsoft Security: May 2026

At Microsoft, security innovations are purpose-built to help every organization protect end-to-end with the speed and scale of AI. Our vision is simple: security should be ambient and autonomous, just like the AI it protects. As organizations accelerate AI adoption, security teams are navigating...

Breaking the code: Multi-stage ‘code of conduct’ phishing campaign leads to AiTM token compromise

In this article 1. Multi-step social engineering campaign leading to credential theft 2. Mitigation and protection guidance 3. Microsoft Defender detections 4. Hunting queries 5. Indicators of compromise Phishing campaigns continue to improve sophistication and refinement in blending social...

Simplifying AWS defense with Microsoft Sentinel UEBA

In this article 1. Under the hood: The tables 2. Traditional vs. new approach 3. Real-world attack scenarios: Microsoft Sentinel UEBA in action 4. Practical implementation: Getting started 5. Limitations and constraints 6. From raw logs to behavioral context With the expansion of Microsoft Sentin...

Malicious AI Assistant Extensions Harvest LLM Chat Histories

Microsoft Defender has been investigating reports of malicious Chromium‑based browser extensions that impersonate legitimate AI assistant tools to harvest LLM chat histories and browsing data. Reporting indicates these extensions have reached approximately 900,000 installs. Microsoft Defender...

Microsoft named a leader in the 2025 Gartner® Magic Quadrant™ for Email Security

We’re honored to share that Microsoft has been named a Leader in the 2025 Gartner® Magic Quadrant™ for Email Security. We believe this recognition highlights the value of Microsoft Defender for Office 365’s innovative capabilities in addressing today’s complex email security challenges. Protect...

Transparency on Microsoft Defender for Office 365 email security effectiveness

In today’s world, cyberattackers are relentless. They are often well-resourced, highly sophisticated, and constantly innovating, which means the effectiveness of cybersecurity solutions must be continuously evaluated, not assumed. Yet, despite the critical role email security plays in protecting...

Microsoft extends Zero Trust to secure the agentic workforce

Microsoft’s 2025 Work Trend Index Read more ↗ Agentic AI transformation is giving rise to the Frontier Firm—a new type of organization characterized by on-demand intelligence and a workforce where humans and agents work in tandem. According to Microsoft’s 2025 Work Trend Index, we expect every...

Explore how to secure AI by attending our Learn Live Series

As organizations develop, use, and increasingly rely on AI applications, they must address new and amplified security risks. Are you prepared to secure your environment for AI adoption? How about identifying threats to your AI and safeguarding data? Register to attend one or all our Learn Live...

Top insights and best practices from the new Microsoft Data Security Index report

A whopping 74 percent of organizations recently surveyed experienced at least one data security incident with their business data exposed in the previous year. That’s just one of our interesting insights from Microsoft’s new Data Security Index: Trends, insights, and strategies to secure data...

Forrester names Microsoft a Leader in the 2023 Zero Trust Platform Providers Wave™ report

Microsoft is proud to be recognized as a Leader in the Forrester Wave™: Zero Trust Platform Providers, Q3 2023 report. At Microsoft, we understand modernizing security is a complex task in this era of ever-evolving cyberthreats and complex digital environments. Serious threats have necessitated a...

Public preview: Improve Win32 app security via app isolation

The post Public preview: Improve Win32 app security via app isolation appeared first on Microsoft Security Blog...

Join our digital event to learn what’s new in Microsoft Entra

Editors note 6/15/2023: This blog has been updated to reflect the new date for this event, which is now July 11, 2023. It was previously scheduled for June 20, 2023. In today’s interconnected world, there’s virtually no limit to what technology can help us achieve. Millions of connections happen...

Do more with less—Discover the latest Microsoft Entra innovations

It has certainly been another intense year. From the ongoing pandemic to the Great Reshuffle to economic uncertainty, it’s truly felt like the only constant is change.1 In this economy, many organizations are looking for efficiencies. This is putting pressure on security teams, along with everyon...

Do more with less—Discover the latest Microsoft Entra innovations

It has certainly been another intense year. From the ongoing pandemic to the Great Reshuffle to economic uncertainty, it’s truly felt like the only constant is change.1 In this economy, many organizations are looking for efficiencies. This is putting pressure on security teams, along with everyon...

CSO perspective: Why a strong IAM strategy is key to an organization’s cybersecurity approach

The security community is continuously changing, growing, and learning from each other to better position the world against cyberthreats. In the latest post of our Community Voices blog series, Microsoft Security Senior Product Marketing Manager Brooke Lynn Weenig talks with Alissa “Dr. Jay”...

One Microsoft manager’s entrepreneurial vision for multicloud identity and access

In July 2021, Microsoft acquired CloudKnox, a leader in cloud infrastructure entitlement management CIEM. Over the past two years, I’ve had the pleasure of getting to know the founder and chief executive officer CEO, Balaji Parimi, who is now the Partner General Manager of Permissions Management ...

3 steps to secure your multicloud and hybrid infrastructure with Azure Arc

As businesses around the world grapple with the growth of an industrialized, organized attacker ecosystem, the need for customers to secure multicloud and hybrid infrastructure and workloads is increasingly urgent. Today, organizations face an attacker ecosystem that is highly economically...

What Generation Z can teach us about cybersecurity

Girl Security National Security Fellows Program fellow Amulya, a 17-year-old interested in countering online disinformation, said she feels her sense of personal privacy has been largely nonexistent “growing up in a media-saturated world.” She believes her sense of privacy was stolen by a...

Microsoft Security delivers new multicloud capabilities

In times of great change, challenges and opportunities can be found in many directions. This is certainly true in IT and cybersecurity. Today, while navigating a pandemic, frequent supply chain shocks, and global talent shortages, organizations around the world are forced to confront sophisticate...

4 best practices to implement a comprehensive Zero Trust security approach

Today’s threat actors don’t see barriers, they see opportunities. As the old firewalls protecting the corporate network become obsolete amid the rush to adopt a hybrid workspace, implementing Zero Trust security has become an imperative across all sectors, both public and private. During this tim...

What you need to know about how cryptography impacts your security strategy

The security community is continuously changing, growing, and learning from each other to better position the world against cyber threats. In the latest post of our Voice of the Community blog series post, Microsoft Security Product Marketing Manager Natalia Godyla talks with Taurus SA Co-founder...

Best practices for AI security risk management

Today, we are releasing an AI security risk assessment framework as a step to empower organizations to reliably audit, track, and improve the security of the AI systems. In addition, we are providing new updates to Counterfit, our open-source tool to simplify assessing the security posture of AI...

Behind the unprecedented effort to protect customers against the NOBELIUM nation-state attack

This is the third in a four-part blog series on the NOBELIUM nation-state cyberattack. In December 2020, Microsoft began sharing details with the world about what became known as the most sophisticated nation-state cyberattack in history. Microsoft’s four-part video series “Decoding NOBELIUM” pul...

3 trends shaping identity as the center of modern security

I recently returned from Kenya, where I visited our Microsoft Nairobi development center. Like many of you, I’ve mostly worked from home for the past year and more, so it was refreshing to meet members of our global team and inspiring to feel their passion for our mission: delivering identity...

Why diversity is important for a strong cybersecurity team

Medicine. Aeronautics. Academia. When you’re a cybersecurity professional, the colleague next to you could have started in one of these industries—or just about any other you can imagine. The backgrounds of cybersecurity professionals are more diverse than those of professionals in other...

Strategies, tools, and frameworks for building an effective threat intelligence team

How to think about building a threat intelligence program The security community is continuously changing, growing, and learning from each other to better position the world against cyber threats. In the latest Voice of the Community blog series post, Microsoft Product Marketing Manager Natalia...

First things first: Envisioning your security deployment

This blog post is part of a series that responds to common questions we receive from customers about deployment of Microsoft 365 Security solutions. In this series youll find context, answers, and guidance for deployment and driving adoption within your organization. Check out our last blog...

Overview of Petya, a rapid cyberattack

In the first blog post of this 3-part series, we introduced what rapid cyberattacks are and illustrated how they are different in terms of execution and outcome. Next, we will go into some more details on the Petya aka NotPetya attack. How Petya worked The Petya attack chain is well understood,...

Chromium extension uses AI‑related branding to redirect browser search

In this article 1. Extension overview 2. Key indicators of malicious behavior 3. Dynamic analysis findings 4. Mitigation and protection guidance 5. References 6. Learn more Microsoft Threat Intelligence has identified a malicious Chromium-based extension that spoofs the AI-powered answer engine...

Photo ZIP campaign targeting hospitality industry delivers Node.js implant for persistent access

In this article 1. Attack chain overview 2. Mitigation and protection guidance 3. References 4. Learn more Microsoft Threat Intelligence has identified an active multi-stage intrusion campaign targeting organizations in the hospitality and hotel industry since April 2026. We’ve observed this...

Crypto Clipper uses Tor and worm-like propagation for persistence and control

In this article 1. Attack chain overview 2. Mitigation and protection guidance 3. References 4. Learn more Microsoft Threat Intelligence and Microsoft Defender Experts identified a Windows-based cryptocurrency clipper that has affected users since February of 2026. Clipper malware relies on...

From poisoned search results to GPU mining: A cryptojacking campaign abusing ScreenConnect and Microsoft .NET utilities

In this article 1. Attack chain overview 2. Mitigation and protection guidance 3. References 4. Learn more Microsoft Defender Experts identified an active cryptojacking campaign in which malicious download sites are surfaced not only through traditional search engine poisoning, but also through A...

Securing the gaming culture of cultures

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...

Exposing Fox Tempest: A malware-signing service operation

In this article 1. Fox Tempest’s role and impact 2. Fox Tempest’s malware signing as a service infrastructure 3. Defending against Fox Tempest-enabled attacks 4. Microsoft Defender detections 5. Indicators of compromise Fox Tempest is a financially motivated threat actor that operates a...

Microsoft Agent 365, now generally available, expands capabilities and integrations

Microsoft Agent 365 Now generally available for commercial customers. Connect with your Microsoft 365 expert Choose an ecosystem partner for agent security and governance AI agents aren’t coming—they’re already in your environment. They show up in places you expect like Microsoft Copilot, Microso...

Dissecting Sapphire Sleet’s macOS intrusion from lure to compromise

In this article 1. Sapphire Sleet’s campaign lifecycle 2. Defending against Sapphire Sleet intrusion activity 3. Microsoft Defender detection and hunting guidance 4. Indicators of compromise Executive summary Microsoft Threat Intelligence uncovered a macOS‑focused cyber campaign by the North Kore...

Developer-targeting campaign using malicious Next.js repositories

Microsoft Defender Experts identified a coordinated developer-targeting campaign delivered through malicious repositories disguised as legitimate Next.js projects and technical assessment materials. Telemetry collected during this investigation indicates the activity aligns with a broader cluster...

SesameOp: Novel backdoor uses OpenAI Assistants API for command and control

Microsoft Incident Response – Detection and Response Team DART researchers uncovered a new backdoor that is notable for its novel use of the OpenAI Assistants Application Programming Interface API as a mechanism for command-and-control C2 communications. Instead of relying on more traditional...

Inside the attack chain: Threat activity targeting Azure Blob Storage

Azure Blob Storage, like any object data service, is a high-value target for threat actors due to its critical role in storing and managing massive amounts of unstructured data at scale across diverse workloads. Organizations of all sizes use Blob Storage to support key workloads—such as AI, high...

Disrupting threats targeting Microsoft Teams

The extensive collaboration features and global adoption of Microsoft Teams make it a high-value target for both cybercriminals and state-sponsored actors. Threat actors abuse its core capabilities – messaging chat, calls and meetings, and video-based screen-sharing – at different points along th...

Marbled Dust leverages zero-day in Output Messenger for regional espionage

Since April 2024, the threat actor that Microsoft Threat Intelligence tracks as Marbled Dust has been observed exploiting user accounts that have not applied fixes to a zero-day vulnerability CVE-2025-27920 in the messaging app Output Messenger, a multiplatform chat software. These exploits have...

An integrated incident response solution with Microsoft and PwC

Today Microsoft Incident Response is excited to announce a new collaboration with PwC to expand our joint incident response and recovery capability. In this global alliance, Microsoft begins the initial containment and investigation, bringing a deep understanding of a company’s infrastructure to...