Be careful of data without context: The case of malware scanning of journaled emails

Recently, we shared details on how effectiveness is measured for Office 365 Exchange Online Protection EOP and Advanced Threat Protection ATP. We also followed up with a comprehensive update on Office 365s improved ability to stop phishing emails from impacting users. These reports highlighted:...

Analysis of cyberattack on U.S. think tanks, non-profits, public sector by unidentified attackers

Reuters recently reported a hacking campaign focused on a wide range of targets across the globe. In the days leading to the Reuters publication, Microsoft researchers were closely tracking the same campaign. Our sensors revealed that the campaign primarily targeted public sector institutions and...

Now that you have a plan, it’s time to start deploying

This blog 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 First...

Azure Sphere—Microsoft’s answer to escalating IoT threats—reaches general availability

Today Azure Sphere—Microsoft’s integrated security solution for IoT devices and equipment—is widely available for the development and deployment of secure, connected devices. Azure Sphere’s general availability milestone couldn’t be timelier. From consumer device hacking and botnets to nation sta...

Uncovering Linux based cyberattack using Azure Security Center

As more and more enterprises move to the cloud, they also bring their own set of security challenges. Today, almost half of Azure virtual machines VMs are running on Linux, and as the Linux server population grows, so are the attacks targeting them. As detection capabilities advance, attackers ar...

From edge appliance to enterprise compromise: Multi-stage Linux intrusion via F5 and Confluence

In this article 1. Attack chain overview 1. Initial access: Exploiting edge appliances 2. Discovery and reconnaissance 3. Lateral movement and identity compromise 2. Mitigation and protection guidance 1. Microsoft Defender XDR detections 2. Advanced hunting 3. Indicators of compromise IOC 4. MITR...

Cross‑tenant helpdesk impersonation to data exfiltration: A human-operated intrusion playbook

In this article 1. Risk to enterprise environments 2. Attack chain overview 1. Stage 1: Initial contact via Teams T1566.003 Spearphishing via Service 2. Stage 2: Remote assistance foothold 3. Stage 3: Interactive reconnaissance and access validation 4. Stage 4: Payload placement and trusted...

Inside an AI‑enabled device code phishing campaign

In this article 1. Attack chain overview 2. Mitigation and protection guidance 3. Indicators of compromise IOC 4. References 5. Learn more Microsoft Defender Security Research has observed a widespread phishing campaign leveraging the Device Code Authentication flow to compromise organizational...

Uncursing the ncurses: Memory corruption vulnerabilities found in library

Microsoft has discovered a set of memory corruption vulnerabilities in a library called ncurses, which provides APIs that support text-based user interfaces TUI. Released in 1993, the ncurses library is commonly used by various programs on Portable Operating System Interface POSIX operating...

New Surface PCs enable virtualization-based security (VBS) by default to empower customers to do more, securely

VBS and HVCI-enabled devices help protect from advanced attacks Escalation of privilege attacks are a malicious actor’s best friend, and they often target sensitive information stored in memory. These kinds of attacks can turn a minor user mode compromise into a full compromise of your OS and...

How to avoid getting caught in a “Groundhog Day” loop of security issues

It’s Cyber Security Awareness Month and it made me think about one of my favorite movies, called Groundhog Day. Have you ever seen it? Bill Murray is the cynical weatherman, Phil Connors, who gets stuck in an endless loop where he repeats the same day over and over again until he “participates in...

How to prevent phishing attacks that target your customers with DMARC and Office 365

You already know that email is the number one attack vector for cybercriminals. But what you might not know is that without a standard email security protocol called Domain Message Authentication, Reporting, and Conformance DMARC, your organization is open to the phishing attacks that target your...

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...

Exploitation of CLFS zero-day leads to ransomware activity

Microsoft Threat Intelligence Center MSTIC and Microsoft Security Response Center MSRC have discovered post-compromise exploitation of a zero-day elevation of privilege vulnerability in the Windows Common Log File System CLFS against a small number of targets. The targets include organizations in...

A better cloud access security broker: Securing your SaaS cloud apps and services with Microsoft Cloud App Security

Today’s business uses an average of 1,180 cloud apps¹, with many of those organizations securing their apps through cloud access security brokers CASB. The organizational need for a CASB has grown alongside the use of cloud apps to enable remote work and greater user productivity. When security...

Identity governance: The power of “Why not?”

Innovation requires the courage to take risks and the leadership skills to show others that risks are worth taking. That’s why I love working with people like Joe Dadzie, a partner group program manager in identity governance. Joe has a long history of championing disruptive technology...

Operational resilience in a remote work world

Microsoft CEO Satya Nadella recently said, “We have seen two years’ worth of digital transformation in two months.” This is a result of many organizations having to adapt to the new world of document sharing and video conferencing as they become distributed organizations overnight. At Microsoft, ...

Microsoft researchers work with Intel Labs to explore new deep learning approaches for malware classification

The opportunities for innovative approaches to threat detection through deep learning, a category of algorithms within the larger framework of machine learning, are vast. Microsoft Threat Protection today uses multiple deep learning-based classifiers that detect advanced threats, for example,...

Decentralized identity and the path to digital privacy

Security is the central challenge of the digital age. Our digital lives have moved into the cloud. People now use multiple devices to connect to multiple applications through many different networks. Just about everything is connected to the internet, where threats remain constant and evolving. I...

Enhancing Office 365 Advanced Threat Protection with detonation-based heuristics and machine learning

Email, coupled with reliable social engineering techniques, continues to be one of the primary entry points for credential phishing, targeted attacks, and commodity malware like ransomware and, increasingly in the last few months, cryptocurrency miners. Office 365 Advanced Threat Protection ATP...

Analyzing CVE-2025-31191: A macOS security-scoped bookmarks-based sandbox escape

In April 2024, Microsoft uncovered a vulnerability in macOS that could allow specially crafted codes to escape the App Sandbox and run unrestricted on the system. An attacker could create an exploit to escape the App Sandbox without user interaction required for any sandboxed app using...

Nation-state threat actor Mint Sandstorm refines tradecraft to attack high-value targets

Over the past several months, Microsoft has observed a mature subgroup of Mint Sandstorm, an Iranian nation-state actor previously tracked as PHOSPHORUS, refining its tactics, techniques, and procedures TTPs. Specifically, this subset has rapidly weaponized N-day vulnerabilities in common...

Threat actor leverages coin miner techniques to stay under the radar – here’s how to spot them

Cryptocurrency miners are typically associated with cybercriminal operations, not sophisticated nation state actor activity. They are not the most sophisticated type of threats, which also means that they are not among the most critical security issues that defenders address with urgency. Recent...

Safeguard your most sensitive data with Microsoft 365

I am Security Operations’ SecOps worst nightmare. Or at least I used to be. As an industrious product marketer, I often share intellectual property think: details of new product capabilities or spreadsheets that contain customer personal identifying information PII with colleagues and vendors. We...

Exposed and vulnerable: Recent attacks highlight critical need to protect internet-exposed OT devices

Since late 2023, Microsoft has observed an increase in reports of attacks focusing on internet-exposed, poorly secured operational technology OT devices. Internet-exposed OT equipment in water and wastewater systems WWS in the US were targeted in multiple attacks over the past months by different...

New Microsoft Sysmon report in VirusTotal improves security

Today, following the 25th year anniversary of Microsoft Sysinternals, we are announcing the general availability of a new Microsoft Sysmon report in VirusTotal. Whether you’re an IT professional or a developer, you’re probably already using Microsoft Sysinternals utilities to help you manage,...

CISO series: Lessons learned from the Microsoft SOC—Part 3a: Choosing SOC tools

The Lessons learned from the Microsoft SOC blog series is designed to share our approach and experience with security operations center SOC operations. Our learnings in the series come primarily from Microsoft’s corporate IT security operation team, one of several specialized teams in the Microso...

Improve security and simplify operations with Windows Defender Antivirus + Morphisec

My team at Morphisec a Microsoft Intelligent Security Association MISA partner often talks with security professionals who are well-informed about the latest cyberthreats and have a longterm security strategy. The problem many of them face is how to create a stronger endpoint stack with limited...

Gartner names Microsoft a Leader in 2019 Endpoint Protection Platforms Magic Quadrant

Our mission as a company is to empower every person on the planet to achieve more. We deliver on that mission through products that achieve the highest marks in the industry, which we believe is inclusive of Gartner’s Magic Quadrant. We have been on a journey for the last several years working ha...

Advancing Windows 10 as a passwordless platform

Passwords can be frustrating, difficult to remember, and easily hacked or stolen. That’s why our vision for Windows is one of a passwordless platform—a world where users don’t have to deal with the pains of a password. With the release of Windows 10, version 1903, we’re bringing Windows 10 closer...

Partnering with the industry to minimize false positives

Every day, antivirus capabilities in Windows Defender Advanced Threat Protection Windows Defender ATP protect millions of customers from threats. To effectively scale protection, Windows Defender ATP uses intelligent systems that combine multiple layers of machine learning models, behavior-based...

Protecting the protector: Hardening machine learning defenses against adversarial attacks

Harnessing the power of machine learning and artificial intelligence has enabled Windows Defender Advanced Threat Protection Windows Defender ATP next-generation protection to stop new malware attacks before they can get started often within milliseconds. These predictive technologies are central...

Cybersecurity Reference Architecture: Security for a Hybrid Enterprise

The Microsoft Cybersecurity Reference Architecture describes Microsofts cybersecurity capabilities and how they integrate with existing security architectures and capabilities. We recently updated this diagram and wanted to share a little bit about the changes and the document itself to help you...

Tapping the intelligent cloud to make security better and easier

There has been a distinct shift in my conversations with customers over the last year. Most have gone from asking can we still keep our assets secure as we adopt cloud services?, to declaring, we are adopting cloud services in order to improve our security posture. The driving factor is generally...

Intent redirection vulnerability in third-party SDK exposed millions of Android wallets to potential risk

In this article 1. Technical details 2. Disclosure timeline 3. Mitigation and protection guidance 4. References 5. Learn more During routine security research, we identified a severe intent redirection vulnerability in a widely used third-party Android SDK called EngageSDK. This flaw allows apps ...

DEV-0832 (Vice Society) opportunistic ransomware campaigns impacting US education sector

In recent months, Microsoft has detected active ransomware and extortion campaigns impacting the global education sector, particularly in the US, by a threat actor we track as DEV-0832, also known as Vice Society. Shifting ransomware payloads over time from BlackCat, QuantumLocker, and Zeppelin,...

Foundations of Microsoft Flow—secure and compliant automation, part 1

Automation services are steadily becoming significant drivers of modern IT, helping improve efficiency and cost effectiveness for organizations. A recent McKinsey survey discovered that “the majority of all respondents 57 percent say their organizations are at least piloting the automation of...

Guide to Developing a National Cybersecurity Strategy—a resource for policymakers to respond to cybersecurity challenges

Nations from every corner of the world are increasingly leveraging digital transformation to grow their economies and empower businesses to improve services, including vital services provided by critical infrastructures. This adoption of new information communications technologies ICT has...

Cybersecurity threats: How to discover, remediate, and mitigate

This blog 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, Protect...

Migrating content from traditional SIEMs to Azure Sentinel

In part two of this three-part series, we covered the five types of side-by-side security information and event management SIEM configurations commonly used during a long-term migration to Microsoft Azure Sentinel. For part three, we’ll be looking at best practices for migrating your data and...

How to cost-effectively manage and secure a mobile ecosystem

Today’s post was written by Roxane Suau, Vice President of Marketing for Pradeo. In the corporate environment, mobile devices and applications are at the center of communications, enhancing collaborators’ productivity with 24/7 access to information. But at the same time, they represent thousands...

New browser extensions for integrating Microsoft’s hardware-based isolation

The hardware-based isolation technology on Windows 10 that allows Microsoft Edge to isolate browser-based attacks is now available as a browser extension for Google Chrome and Mozilla Firefox. We introduced the container technology in 2017. Since then, we have been evolving the technology and...

Voice of the Customer: Walmart embraces the cloud with Azure Active Directory

Todays post was written by Sue Bohn, partner director of Program Management and Ben Byford and Gerald Corson, senior directors of Identity and Access Management at Walmart. Greetings! Im Sue Bohn, partner director of Program Management at Microsoft. Im an insatiable, lifelong learner and I lead t...

The final compliance countdown: Are you ready for GDPR?

On May 25, the General Data Protection Regulation GDPR will replace the Data Protection Directive as the new standard on data privacy for all organizations that do business with European Union EU citizens.1When GDPR goes into effect, government agencies and organizations that control, maintain, o...

The role that regions can and should play in critical infrastructure protection

Todays report, Critical Infrastructure Protection in Latin America and the Caribbean 2018, developed in partnership between Microsoft and the Organization of American States OAS, demonstrates the value of regional cooperation in global efforts to increase the security of the online environment...

Cyber Signals: Inside the growing risk of gift card fraud

In the ever-evolving landscape of cyberthreats, staying ahead of malicious actors is a constant challenge. Microsoft Threat Intelligence has observed that gift cards are attractive targets for fraud and social engineering practices. Unlike credit or debit cards, there’s no customer name or bank...

How to gain 24/7 detection and response coverage with Microsoft Defender ATP

This blog post is part of the Microsoft Intelligence Security Association guest blog series. To learn more about MISA, go...

The evolution of Microsoft Threat Protection—July update

Modern security teams need to proactively, efficiently, and effectively hunt for threats across multiple attack vectors. To address this need, today we’re excited to give you a glimpse of a new threat hunting capability coming soon to Microsoft Threat Protection. Building off the threat hunting...

Introducing the security configuration framework: A prioritized guide to hardening Windows 10

In the past, we left defining the security configuration for Windows 10 as a task for every customer to sort out. As a result, we saw as many different configurations as we saw customers. Standardization has many advantages, so we developed a security configuration framework to help simplify...

Step 1. Identify users: top 10 actions to secure your environment

This series outlines the most fundamental steps you can take with your investment in Microsoft 365 security solutions. Well provide advice on activities such as setting up identity management through active directory, malware protection, and more. In this post, we explain how to create a single...