How the Microsoft Incident Response team helps customers remediate threats

Each year, organizations face tens of billions of malware, phishing, and credential threats—with real-world impacts. When an attack succeeds, it can result in grave impacts on any industry. For example, it could delay a police or fire department’s response to an emergency, prevent a hospital from...

New Microsoft Security innovations expand multicloud visibility and enhance multiplatform protection

With more than 90 percent of organizations adopting a multicloud strategy1 and cloud-based cyberattacks growing 48 percent year over year,2 securing multicloud and hybrid environments is more important than ever. To successfully protect multicloud infrastructure—where customers are utilizing two ...

Mini Shai Hulud: Compromised @antv npm packages enable CI/CD credential theft

In this article 1. Attack chain overview 1. Technical analysis 2. How GitHub took action to prevent further harm 2. Mitigation and protection guidance 1. Microsoft Defender XDR Detections 2. Microsoft Defender XDR Threat analytics 3. Advanced hunting 4. Indicators of Compromise IOC 3. References ...

Accelerating detection engineering using AI-assisted synthetic attack logs generation

In this article 1. Core Idea: From TTPs to Logs 2. Approaches for Synthetic Attack Log Generation 3. Evaluation Datasets 4. References 5. Learn more Logs and telemetry are the foundation of modern cybersecurity. They enable threat detection, incident response, forensic investigation, and complian...

Accelerating detection engineering using AI-assisted synthetic attack logs generation

In this article 1. Core Idea: From TTPs to Logs 2. Approaches for Synthetic Attack Log Generation 3. Evaluation Datasets 4. References 5. Learn more Logs and telemetry are the foundation of modern cybersecurity. They enable threat detection, incident response, forensic investigation, and complian...

Defending consumer web properties against modern DDoS attacks

If you own, create, or maintain online services and web portals, you’re probably aware of the dramatic upswing in DDoS attacks on your domains. AI has democratized tooling not just for us but for threat actors as well. DDoS in this era has extended from simple bandwidth saturation to sophisticate...

Undermining the trust boundary: Investigating a stealthy intrusion through third-party compromise

In this article 1. Abuse of trusted relationships as an attack delivery mechanism 2. Methods, tools, and access strategies 3. Campaign conclusion 4. Microsoft Defender detection and hunting guidance In recent years, many sophisticated intrusions have increasingly avoided using noisy exploits,...

When prompts become shells: RCE vulnerabilities in AI agent frameworks

In this article 1. A representative case study: Semantic Kernel 2. CVE-2026-26030: In-Memory Vector Store 3. CVE-2026-25592: Arbitrary file write through SessionsPythonPlugin 4. The vulnerability 5. Attack chain overview 6. Defending the agentic edge 7. Not bugs, but developed by design 8. CTF...

World Passkey Day: Advancing passwordless authentication

World Passkey Day is a chance to reflect on progress toward a shared goal: reducing our reliance on passwords and other phishable authentication methods by accelerating passkey adoption. As cyberattacks become more automated and AI-powered, each account is only as secure as its weakest credential...

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...

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...

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...

Threat actor abuse of AI accelerates from tool to cyberattack surface

For the last year, one word has represented the conversation living at the intersection of AI and cybersecurity: speed. Speed matters, but it’s not the most important shift we are observing across the threat landscape today. Now, threat actors from nation states to cybercrime groups are embedding...

Mitigating the Axios npm supply chain compromise

In this article 1. Analysis of the attack 2. Mitigation and protection guidance 3. Microsoft Defender detections 4. Indicators of compromise 5. Hunting queries On March 31, 2026, two new npm packages for updated versions of Axios, a popular HTTP client for JavaScript that simplifies making HTTP...

WhatsApp malware campaign delivers VBScript and MSI backdoors

In this article 1. Attack chain overview 2. Mitigation and protection guidance 3. Hunting queries 4. Indicators of compromise Microsoft Defender Experts observed a campaign beginning in late February 2026 that uses WhatsApp messages to deliver malicious Visual Basic Script VBS files. Once execute...

Case study: How predictive shielding in Defender stopped GPO-based ransomware before it started

In this article 1. The growing threat: GPO abuse in ransomware operations 2. The incident 3. The results 4. The hardening dilemma: Why threat actors love operational mechanisms 5. Predictive shielding: Contextual, just-in-time hardening 6. Closing the gap 7. References Summary Microsoft Defender...

From transparency to action: What the latest Microsoft email security benchmark reveals

In our last benchmarking post, Clarity in complexity: New insights for transparent email security ,1 we shared why transparency matters more than ever in email security and how clear, consistent benchmarking helps security teams cut through noise and make confident decisions. Today, we’re...

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...

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...

Top 10 actions to build agents securely with Microsoft Copilot Studio

Organizations are rapidly adopting Copilot Studio agents, but threat actors are equally fast at exploiting misconfigured AI workflows. Mis-sharing, unsafe orchestration, and weak authentication create new identity and data‑access paths that traditional controls don’t monitor. As AI agents become...

A one-prompt attack that breaks LLM safety alignment

Large language models LLMs and diffusion models now power a wide range of applications, from document assistance to text-to-image generation, and users increasingly expect these systems to be safety-aligned by default. Yet safety alignment is only as robust as its weakest failure mode. Despite...

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...

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,...

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...

Investigating targeted “payroll pirate” attacks affecting US universities

Microsoft Threat Intelligence has observed a financially motivated threat actor that we track as Storm-2657 compromising employee accounts to gain unauthorized access to employee profiles and divert salary payments to attacker-controlled accounts. These types of attacks have been dubbed “payroll...

Retail at risk: How one alert uncovered a persistent cyberthreat​​

In the latest edition of our Cyberattack Series, we dive into real-world cases targeting retail organizations. With 60% of retail companies reporting operational disruptions from cyberattacks and 43% experiencing security compromises in the past year, the risks for businesses continue to increase...

Microsoft Purview delivered 30% reduction in data breach likelihood

In today’s digital-first world, data is both an asset and a liability. As organizations scale their use of cloud platforms, AI, and remote collaboration tools, the complexity of managing data security, data privacy, and regulatory compliance grows exponentially. For organizations, the challenge i...

Storm-0501’s evolving techniques lead to cloud-based ransomware

Microsoft Threat Intelligence has observed financially motivated threat actor Storm-0501 continuously evolving their campaigns to achieve sharpened focus on cloud-based tactics, techniques, and procedures TTPs. While the threat actor has been known for targeting hybrid cloud environments, their...

Quantum-safe security: Progress towards next-generation cryptography

Quantum computing promises transformative advancements, yet it also poses a very real risk to today’s cryptographic security. In the future scalable quantum computing could break public-key cryptography methods currently in use and undermine digital signatures, resulting in compromised...

Announcing public preview: Phishing triage agent in Microsoft Defender

Intelligent triage for a more agile, autonomous SOC At Microsoft Secure 2025, we introduced a new wave of innovations across Microsoft Defender aimed at redefining what AI can do for security operations. At the center of these announcements was the launch of 11 Security Copilot agents, each...

Sharing practical guidance: Launching Microsoft Secure Future Initiative (SFI) patterns and practices

We’re excited to launch Microsoft Secure Future Initiative SFI patterns and practices : a new library of actionable guidance designed to help organizations implement security measures at scale. This launch marks the next step in our journey to make our SFI learnings practical for our customers,...

Microsoft is named a Leader in the 2025 Gartner® Magic Quadrant™ for Endpoint Protection Platforms

Since 2022, the number of human-operated ransomware-linked encounters by organizations surged by 2.75x. Yet, Microsoft Defender for Endpoint has outpaced this rise, reducing the number of successful attacks by 3x, proving its power to turn the tide against evolving cyberthreats.1 Defender for...

Planning your move to Microsoft Defender portal for all Microsoft Sentinel customers

In November 2023, Microsoft announced our strategy to unify security operations by bringing the best of XDR and SIEM together. Our first step was bringing Microsoft Sentinel into the Defender portal, giving teams a single, comprehensive view of incidents, reducing queue management, enriched threa...

Microsoft Named a Leader in the 2025 IDC CNAPP MarketScape: Key Takeaways for Security Buyers

The cloud-native application protection platform CNAPP market continues to evolve rapidly as organizations look to secure increasingly complex cloud environments. In the recently published 2025 IDC MarketScape for Worldwide CNAPP, Microsoft has been recognized as a Leader, reaffirming its...

Cyber resilience begins before the crisis

In this blog you will hear directly from Microsoft’s Deputy Chief Information Security Officer CISO for Customer Security, Ann Johnson, about the need for proactive planning in cyber incidents, particularly surrounding communications. This blog is part of a new, ongoing series where our Deputy...

Meet the Deputy CISOs who help shape Microsoft’s approach to cybersecurity: Part 3

Microsoft launched its Cybersecurity Governance Council in 2024, and with it, named a group of deputy chief information security officers that ensure comprehensive oversight of the company’s cybersecurity risk, defense, and compliance. These leaders work in tandem with product and engineering...

14 secure coding tips: Learn from the experts at Microsoft Build

Hey friends! If you are a developer, you know that writing clean and efficient code is just the starting point. Now, with AI playing a bigger role, secure coding isn't just a 'nice-to-have'—it's a must. Whether you're building web apps, working on cloud services, or adding AI to your projects,...

Microsoft announces the 2025 Security Excellence Awards winners

In today’s rapidly evolving digital world, security requires a global community of defenders working together as a team to build a safer world for all. That’s why we’re thrilled to recognize the extraordinary individuals and organizations who have gone above and beyond in the fight against...

Microsoft’s Secure by Design journey: One year of success

Cybersecurity is one of the top risks facing businesses. Organizations are struggling to navigate the ever-evolving cyberthreat landscape in which 600 million identity attacks are carried out daily.1 The median time for a cyberattacker to access private data from phishing is 1 hour and 12 minutes...

Meet the Deputy CISOs who help shape Microsoft’s approach to cybersecurity

Microsoft launched its Cybersecurity Governance Council in 2024, and with it, named a group of deputy chief information security officers that ensure comprehensive oversight of the company's cybersecurity risk, defense, and compliance. These leaders work in tandem with product and engineering...

Microsoft unveils Microsoft Security Copilot agents and new protections for AI

In this age of AI, securing AI and using it to boost security are crucial for every organization. At Microsoft, we are dedicated to helping organizations secure their future with our AI-first, end-to-end security platform. One year ago, we launched Microsoft Security Copilot to empower defenders ...

AI innovation requires AI security: Hear what’s new at Microsoft Secure

When you’re secure—innovation happens. But, the fast pace of AI often outpaces traditional security measures, leaving gaps that bad actors can take advantage of. As a security professional, you’re the hero in this battle between protecting vast amounts of data while ensuring AI systems remain...

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...

How Storm-2949 turned a compromised identity into a cloud-wide breach

In this article 1. Attack chain overview 1. Cloud compromise: Microsoft Entra ID and Microsoft 365 2. Initial access and persistence through targeted social engineering and SSPR abuse 3. Directory discovery and persistence 4. Microsoft 365 discovery and exfiltration 5. Cloud compromise: Microsoft...

How to better protect your growing business in an AI-powered world

AI is rapidly reshaping how work gets done in companies and organizations. In celebrating National Small Business Month, we want to acknowledge the unique challenges that growing business leaders face as AI creates both opportunity and risk. They face constant tradeoffs between moving fast,...

When configuration becomes a vulnerability: Exploitable misconfigurations in AI apps

In this article 1. Background 2. What is an exploitable misconfiguration? 3. Exploitable misconfigurations in popular AI applications 4. Minimizing the risk: Practical deployment guidance 5. How Microsoft Defender for Cloud helps detect exposures in Kubernetes 6. Learn more AI and agentic...

When configuration becomes a vulnerability: Exploitable misconfigurations in AI apps

In this article 1. Background 2. What is an exploitable misconfiguration? 3. Exploitable misconfigurations in popular AI applications 4. Minimizing the risk: Practical deployment guidance 5. How Microsoft Defender for Cloud helps detect exposures in Kubernetes 6. Learn more AI and agentic...

Undermining the trust boundary: Investigating a stealthy intrusion through third-party compromise

In this article 1. Abuse of trusted relationships as an attack delivery mechanism 2. Methods, tools, and access strategies 3. Campaign conclusion 4. Microsoft Defender detection and hunting guidance In recent years, many sophisticated intrusions have increasingly avoided using noisy exploits,...

Active attack: Dirty Frag Linux vulnerability expands post-compromise risk

In this article 1. Why Dirty Frag matters 2. Technical overview 3. Exploitation scenarios 4. Mitigation guidance 5. Post-mitigation integrity verification 6. References A newly disclosed Linux local privilege escalation vulnerability known as “Dirty Frag” enables escalation from an unprivileged...

When prompts become shells: RCE vulnerabilities in AI agent frameworks

In this article 1. A representative case study: Semantic Kernel 2. CVE-2026-26030: In-Memory Vector Store 3. CVE-2026-25592: Arbitrary file write through SessionsPythonPlugin 4. The vulnerability 5. Attack chain overview 6. Defending the agentic edge 7. Not bugs, but developed by design 8. CTF...