Using Microsoft 365 Defender to protect against Solorigate

Microsoft security researchers continue to investigate and respond to the sophisticated cyberattack known as Solorigate also referred to as Sunburst by FireEye involving a supply chain compromise and the subsequent compromise of cloud assets. While the related investigations and impact assessment...

Attackers use Morse code, other encryption methods in evasive phishing campaign

Cybercriminals attempt to change tactics as fast as security and protection technologies do. During our year-long investigation of a targeted, invoice-themed XLS.HTML phishing campaign, attackers changed obfuscation and encryption mechanisms every 37 days on average, demonstrating high motivation...

Combing through the fuzz: Using fuzzy hashing and deep learning to counter malware detection evasion techniques

Today’s cybersecurity threats continue to find ways to fly and stay under the radar. Cybercriminals use polymorphic malware because a slight change in the binary code or script could allow the said threats to avoid detection by traditional antivirus software. Threat actors customize their wares...

Spotting brand impersonation with Swin transformers and Siamese neural networks

Every day, Microsoft Defender for Office 365 encounters millions of brand impersonation emails. Our security solutions use multiple detection and prevention techniques to help users avoid divulging sensitive information to phishers as attackers continue refining their impersonation tricks. In thi...

Microsoft Security—a Leader in 5 Gartner Magic Quadrants

Gartner has named Microsoft Security a Leader in five Magic Quadrants. This is exciting news that we believe speaks to the breadth and depth of our security offerings. Gartner places vendors as Leaders who demonstrate balanced progress and effort in all execution and vision categories. This means...

Microsoft discovers threat actor targeting SolarWinds Serv-U software with 0-day exploit

Microsoft has detected a 0-day remote code execution exploit being used to attack SolarWinds Serv-U FTP software in limited and targeted attacks. The Microsoft Threat Intelligence Center MSTIC attributes this campaign with high confidence to DEV-0322, a group operating out of China, based on...

Build a stronger cybersecurity team through diversity and training

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, Microsoft Security Product Marketing Manager Natalia Godyla talks with Heath Adams, Chief...

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...

A playbook for modernizing security operations

The security community is continuously changing, growing, and learning from each other to better position the world against cyber threats. In the latest post from our new Voice of the Community blog series, Microsoft Product Marketing Manager Natalia Godyla talks with Dave Kennedy, Founder and...

Deep dive into the Solorigate second-stage activation: From SUNBURST to TEARDROP and Raindrop

More than a month into the discovery of Solorigate, investigations continue to unearth new details that prove it is one of the most sophisticated and protracted intrusion attacks of the decade. Our continued analysis of threat data shows that the attackers behind Solorigate are skilled campaign...

Privacy compliance for smart meter infrastructure with Microsoft Information Protection and Azure Purview

Smart meters and smart grid infrastructure have been deployed in many of the world’s electric distribution grids. They promise energy conservation, better grid management for utilities, electricity theft reduction, and a host of value-added services for consumers. To deliver on this promise, they...

odix and Microsoft: Protecting users against malware attacks with free FileWall license

This blog post is part of the Microsoft Intelligent Security Association MISA guest blog series. Learn more about MISA. The fight against malware has become the epic battle of our generation, placing businesses of all sizes against a never-ending stream of hackers and zero-day attacks bent on...

Business email compromise campaign targets wide range of orgs with gift card scam

Cybercriminals continue to target businesses to trick recipients into approving payments, transferring funds, or, in this case, purchasing gift cards. This kind of email attack is called business email compromise BEC—a damaging form of phishing designed to gain access to critical business...

A guide to balancing external threats and insider risk

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 Godyla talks with Rockwell Automation Vice President and...

Attack matrix for Kubernetes

Kubernetes, the most popular container orchestration system and one of the fastest-growing projects in the history of open source, becomes a significant part of many companies’ compute stack. The flexibility and scalability of containers encourage many developers to move their workloads to...

Breaking down NOBELIUM’s latest early-stage toolset

As we reported in earlier blog posts, the threat actor NOBELIUM recently intensified an email-based attack that it has been operating and evolving since early 2021. We continue to monitor this active attack and intend to post additional details as they become available. In this blog, we highlight...

Business email compromise: How Microsoft is combating this costly threat

Amongst all cybercrime, phishing attacks continue to be the most prevalent today. With over 90 percent of attacks coming via email, it’s important that every organization has a plan to prevent these threats from reaching users. At Microsoft, we’re passionate about providing our customers with...

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...

ZINC attacks against security researchers

In recent months, Microsoft has detected cyberattacks targeting security researchers by an actor we track as ZINC. The campaign originally came to our attention after Microsoft Defender for Endpoint detected an attack in progress. Observed targeting includes pen testers, private offensive securit...

How to build a privacy program the right way

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 Godyla talks with attorney Whitney Merrill, an expert on...

GoldMax, GoldFinder, and Sibot: Analyzing NOBELIUM’s layered persistence

Microsoft continues to work with partners and customers to expand our knowledge of the threat actor behind the nation-state cyberattacks that compromised the supply chain of SolarWinds and impacted multiple other organizations. As we have shared previously, we have observed the threat actor using...

5 principles driving a customer-obsessed identity strategy at Microsoft

The cloud era has fundamentally changed the way businesses must think about security. For a long time, we built security around the perimeter. But today, the boundaryless landscape demands that we start with the individual. In our journey with customers co-designing our products and services,...

Attack uses malicious InPage document and outdated VLC media player to give attackers backdoor access to targets

Our analysis of a targeted attack that used a language-specific word processor shows why its important to understand and protect against small-scale and localized attacks as well as broad-scale malware campaigns. The attack exploited a vulnerability in InPage, a word processor software for specif...

Assessing Microsoft 365 security solutions using the NIST Cybersecurity Framework

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 blogNew...

Windows Defender Antivirus can now run in a sandbox

Windows Defender Antivirus has hit a new milestone: the built-in antivirus capabilities on Windows can now run within a sandbox. With this new development, Windows Defender Antivirus becomes the first complete antivirus solution to have this capability and continues to lead the industry in raisin...

AutoJack: How a single page can RCE the host running your AI agent

In this article 1. Why we are looking at agent frameworks 1. What is AutoGen Studio 2. The AutoJack chain at a glance 3. Anatomy of the chain 1. Issue 1: Origin allowlist that the agent itself defeats 2. Issue 2: Auth middleware that opts MCP out 3. Issue 3: serverparamsfrom the URL is the comman...

Understanding the threat landscape and risks of OT environments

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 Godyla talks with Chris Sistrunk, Technical Manager in...

MITRE ATT&CK APT 29 evaluation proves Microsoft Threat Protection provides deeper end to end view of advanced threats

As attackers use more advanced techniques, it’s even more important that defenders have visibility not just into each of the domains in their environment, but also across them to piece together coordinated, targeted, and advanced attacks. This level of visibility will allow us to get ahead of...

Best practices for adding layered security to Azure security with Check Point’s CloudGuard IaaS

The cloud is changing the way we build and deploy applications. Most enterprises will benefit from the cloud’s many advantages through hybrid, multi, or standalone cloud architectures. A recent report showed that 42 percent of companies have a multi-cloud deployment strategy. The advantages of th...

Vulnerable SDK components lead to supply chain risks in IoT and OT environments

December 8, 2022 update - Reflected additional research on Boa-related CVEs and updated supply chain diagram. Vulnerabilities in network components, architecture files, and developer tools have become increasingly popular attack vectors to gain access into secure networks and devices. External...

5 steps to enable your corporate SOC to rapidly detect and respond to IoT/OT threats

As organizations connect massive numbers of IoT/OT devices to their networks to optimize operations, boards and management teams are increasingly concerned about the expanding attack surface and corporate liability that they represent. These connected devices can be compromised by adversaries to...

UK launches cyberstrategy with long-term relevance

Like most major global economies, the United Kingdom continues to place cybersecurity issues front and center. The National Cyber Security Strategy: 2016-2021 document—published by the UK Government and released nearly two years ago—describes the plan to make the UK secure and resilient in...

Uncovering Trickbot’s use of IoT devices in command-and-control infrastructure

Trickbot, a sophisticated trojan that has evolved significantly since its discovery in 2016, has continually expanded its capabilities and, even with disruption efforts and news of its infrastructure going offline, it has managed to remain one of the most persistent threats in recent years. The...

A deep-dive into the SolarWinds Serv-U SSH vulnerability

Several weeks ago, Microsoft detected a 0-day remote code execution exploit being used to attack the SolarWinds Serv-U FTP software in limited and targeted attacks. The Microsoft Threat Intelligence Center MSTIC attributed the attack with high confidence to DEV-0322, a group operating out of Chin...

Dismantling a fileless campaign: Microsoft Defender ATP’s Antivirus exposes Astaroth attack

The prevailing perception about fileless threats, among the security industry’s biggest areas of concern today, is that security solutions are helpless against these supposedly invincible threats. Because fileless attacks run the payload directly in memory or leverage legitimate system tools to r...

Securing CI/CD in an agentic world: Claude Code Github action case

Microsoft Threat Intelligence discovered that Anthropic's Claude Code GitHub Action could expose CI/CD workflow secrets when AI agents process untrusted GitHub content, including issue bodies, pull request descriptions, and comments. We found that while Claude Code Action supported environment...

Jasper Sleet: North Korean remote IT workers’ evolving tactics to infiltrate organizations

Since 2024, Microsoft Threat Intelligence has observed remote information technology IT workers deployed by North Korea leveraging AI to improve the scale and sophistication of their operations, steal data, and generate revenue for the Democratic People’s Republic of Korea DPRK. Among the changes...

Microsoft investigates Iranian attacks against the Albanian government

Shortly after the destructive cyberattacks against the Albanian government in mid-July, the Microsoft Detection and Response Team DART was engaged by the Albanian government to lead an investigation into the attacks. At the time of the attacks and our engagement by the Albanian government,...

Inside out: Get to know the advanced technologies at the core of Microsoft Defender ATP next generation protection

While Windows Defender Antivirus makes catching 5 billion threats on devices every month look easy, multiple advanced detection and prevention technologies work under the hood to make this happen. Windows Defender Antivirus is the next-generation protection component of Microsoft Defender Advance...

CTI-REALM: A new benchmark for end-to-end detection rule generation with AI agents

Excerpt: CTI-REALM is Microsoft’s open-source benchmark for evaluating AI agents on real-world detection engineering—turning cyber threat intelligence CTI into validated detections. Instead of measuring “CTI trivia,” CTI-REALM tests end-to-end workflows: reading threat reports, exploring telemetr...

Recent enhancements for Microsoft Power Platform governance

An emerging trend in digital transformation efforts has been the rise of low-code development platforms. Of course, these low-code platforms must be grounded in best-of-breed governance capabilities which include security and compliance features. Without strong governance, the full benefits of...

ChainDrop supply chain compromise: Anatomy of a self-propagating worm

In this article 1. Attack chain overview 2. Mitigation and protection guidance 3. Indicators of compromise IOC 4. Microsoft Defender XDR detections 5. Advanced hunting queries 6. Learn more Microsoft Threat Intelligence identified a large-scale npm supply chain attack affecting more than 400...

Protecting on-premises Exchange Servers against recent attacks

For the past few weeks, Microsoft and others in the security industry have seen an increase in attacks against on-premises Exchange servers. The target of these attacks is a type of email server most often used by small and medium-sized businesses, although larger organizations with on-premises...

Running OpenClaw safely: identity, isolation, and runtime risk

Self-hosted agent runtimes like OpenClaw are showing up fast in enterprise pilots, and they introduce a blunt reality: OpenClaw includes limited built-in security controls. The runtime can ingest untrusted text, download and execute skills i.e. code from external sources, and perform actions usin...

Step 9. Protect your OS: top 10 actions to secure your environment

In “Step 9. Protect your OS” of the Top 10 actions to secure your environment blog series, we provide resources to help you configure Microsoft Defender Advanced Threat Protection Microsoft Defender ATP to defend your Windows, macOS, Linux, iOS, and Android devices from advanced threats. In an...

Hunting down Dofoil with Windows Defender ATP

Dofoil is a sophisticated threat that attempted to install coin miner malware on hundreds of thousands of computers in March, 2018. In previous blog posts we detailed how behavior monitoring and machine learning in Windows Defender AV protected customers from a massive Dofoil outbreak that we...

MERCURY and DEV-1084: Destructive attack on hybrid environment

April 2023 update – Microsoft Threat Intelligence has shifted to a new threat actor naming taxonomy aligned around the theme of weather. MERCURY is now tracked as Mango Sandstorm and DEV-1084 is now tracked as Storm-1084. To learn more about the new taxonomy represents the origin, unique traits,...

Automating and operationalizing data protection with Dataguise and Microsoft Information Protection

This blog post is part of the Microsoft Intelligent Security Association guest blog series. Learn more about MISA. In technical literature, the terms data discovery, classification, and tagging are sometimes used interchangeably, but there are real differences in what they actually mean—and each...

Analyzing Solorigate, the compromised DLL file that started a sophisticated cyberattack, and how Microsoft Defender helps protect customers

We, along with the security industry and our partners, continue to investigate the extent of the Solorigate attack. While investigations are underway, we want to provide the defender community with intelligence to understand the scope, impact, remediation guidance, and product detections and...

A case study in industry collaboration: Poisoned RDP vulnerability disclosure and response

Earlier this year, I reached out to Check Point researcher Eyal Itkin, who had published multiple flaws in several Remote Desktop Protocol RDP clients, including a vulnerability in mstsc.exe, the built-in RDP client application in Windows. While there were no active exploits detected in the wild,...