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Microsoft Secure

Out of sight but not invisible: Defeating fileless malware with behavior monitoring, AMSI, and next-gen AV

Removing the need for files is the next progression of attacker techniques. While fileless techniques used to be employed almost exclusively in sophisticated cyberattacks, they are now becoming widespread in common malware, too....

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Small businesses targeted by highly localized Ursnif campaign

In social engineering attacks, is less really more? A new malware campaign puts that to the test by targeting home users and small businesses in specific US cities. This was a focused, highly localized attack that aimed to steal sensitive info from just under 200 targets. Macro-laced documents masqueraded as statements from legitimate businesses. The...

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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 detection algorithms, generics, and heuristics that make a verdict on suspicious files, most of the time in...

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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 to scaling protection and delivering effective threat prevention in the face of unrelenting attacker activity....

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Protecting the modern workplace from a wide range of undesirable software

Security is a fundamental component of the trusted and productive Windows experience that we deliver to customers through modern platforms like Windows 10 and Windows 10 in S mode. As we build intelligent security technologies that protect the modern workplace, we aim to always ensure that customers have control over their devices and experiences. To...

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Attack inception: Compromised supply chain within a supply chain poses new risks

Attack inception: Compromised supply chain within a supply chain poses new risks

A new software supply chain attack unearthed by Windows Defender Advanced Threat Protection (Windows Defender ATP) emerged as an unusual multi-tier case. Unknown attackers compromised the shared infrastructure in place between the vendor of a PDF editor application and one of its software vendor partners, making the app’s legitimate installer the unsuspecting carrier of a...

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March-April 2018 test results: More insights into industry AV tests

In a previous post, in the spirit of our commitment to delivering industry-leading protection, customer choice, and transparency on the quality of our solutions, we shared insights and context into the results of AV-TEST’s January-February 2018 test cycle. We released a transparency report to help our customers and the broader security community to stay informed...

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Taking apart a double zero-day sample discovered in joint hunt with ESET

In late March 2018, I analyzed an interesting PDF sample found by ESET senior malware researcher Anton Cherepanov. The sample was initially reported to Microsoft as a potential exploit for an unknown Windows kernel vulnerability. During my investigation in parallel with ESET researchers, I was surprised to discover two new zero-day exploits in the same PDF....

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Machine learning vs. social engineering

Machine learning is a key driver in the constant evolution of security technologies at Microsoft. Machine learning allows Microsoft 365 to scale next-gen protection capabilities and enhance cloud-based, real-time blocking of new and unknown threats. Just in the last few months, machine learning has helped us to protect hundreds of thousands of customers against ransomware,...

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Virtualization-based security (VBS) memory enclaves: Data protection through isolation

The escalating sophistication of cyberattacks is marked by the increased use of kernel-level exploits that attempt to run malware with the highest privileges and evade security solutions and software sandboxes. Kernel exploits famously gave the WannaCry and Petya ransomware remote code execution capability, resulting in widescale global outbreaks. Windows 10 remained resilient to these attacks,...

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