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Microsoft Secure

Now you see me: Exposing fileless malware

  (Note: For a comprehensive categorization of fileless malware and a complete list of Microsoft technologies that can protect against these elusive threats, read the latest blog post: Out of sight but not invisible: Defeating fileless malware with behavior monitoring, AMSI, and next-gen AV)   What exactly is fileless? Read latest blog post: Out of sight but...

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A worthy upgrade: Next-gen security on Windows 10 proves resilient against ransomware outbreaks in 2017

Adopting reliable attack methods and techniques borrowed from more evolved threat types, ransomware attained new levels of reach and damage in 2017. The following trends characterize the ransomware narrative in the past year: Three global outbreaks showed the force of ransomware in making real-world impact, affecting corporate networks and bringing down critical services like hospitals,...

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Detonating a bad rabbit: Windows Defender Antivirus and layered machine learning defenses

Windows Defender Antivirus uses a layered approach to protection: tiers of advanced automation and machine learning models evaluate files in order to reach a verdict on suspected malware. While Windows Defender AV detects a vast majority of new malware files at first sight, we always strive to further close the gap between malware release and...

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Microsoft teams up with law enforcement and other partners to disrupt Gamarue (Andromeda)

Today, with help from Microsoft security researchers, law enforcement agencies around the globe, in cooperation with Microsoft Digital Crimes Unit (DCU), announced the disruption of Gamarue, a widely distributed malware that has been used in networks of infected computers collectively called the Andromeda botnet. The disruption is the culmination of a journey that started in...

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Exploring the crypt: Analysis of the WannaCrypt ransomware SMB exploit propagation

On May 12, there was a major outbreak of WannaCrypt ransomware. WannaCrypt directly borrowed exploit code from the ETERNALBLUE exploit and the DoublePulsar backdoor module leaked in April by a group calling itself Shadow Brokers. The trend towards increasingly sophisticated malware behavior, highlighted by the use of exploits and other attack vectors, makes older platforms...

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Windows 10 platform resilience against the Petya ransomware attack

The trend towards increasingly sophisticated malware behavior, highlighted by the use of exploits and other attack vectors, makes older platforms so much more susceptible to ransomware attacks. From June to November 2017, Windows 7 devices were 3.4 times more likely to encounter ransomware compared to Windows 10 devices. Read our latest report: A worthy upgrade:...

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Analysis of the Shadow Brokers release and mitigation with Windows 10 virtualization-based security

On April 14, a group calling themselves the Shadow Brokers caught the attention of the security community by releasing a set of weaponized exploits. Shortly thereafter, one of these exploits was used to create wormable malware that we now know as WannaCrypt, which targeted a large number of out-of-date systems and held encrypted files for...

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MSRT June 2017: Removing sneaky Xiazai

Protecting the modern workplace from a wide range of undesirable software Our evaluation criteria describe the characteristics and behavior of malware and potentially unwanted applications and guide the proper identification of threats. Learn how we classify malicious software, unwanted software, and potentially unwanted applications. Read the blog post. In the June release of the Microsoft...

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Double-click me not: Malicious proxy settings in OLE Embedded Script

Modern social engineering attacks use non-portable executable (PE) files like malicious scripts and macro-laced documents. Every month, Windows Defender AV detects non-PE threats on over 10 million machines. Learn how machine learning drives next-gen protection capabilities and cloud-based, real-time blocking of new and unknown threats: Machine learning vs. social engineering Attackers have been using social...

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Reverse engineering DUBNIUM – Stage 2 payload analysis

Recently, we blogged about the basic functionality and features of the DUBNIUM advanced persistent threat (APT) activity group Stage 1 binary and Adobe Flash exploit used during the December 2015 incident (Part 1, Part 2). In this blog, we will go through the overall infection chain structure and the Stage 2 executable details. Stage 2...

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