An Armful of CHERIs

Today, Arm announced that the first silicon supporting the Morello prototype architecture, a research project led by Arm, Microsoft, University of Cambridge and others, is now available on a limited run of demonstration boards, which are being shipped from today to industry partners for testing...

Coming Soon: New Security Update Guide Notification System

Sharing information through the Security Update Guide is an important part of our ongoing effort to help customers manage security risks and keep systems protected. Based on your feedback we have been working to make signing up for and receiving Security Update Guide notifications easier. We are...

We’re Excited to Announce the Launch of Comms Hub!

We are excited to announce the launch of Comms Hub to the Researcher Portal submission experience! With this launch, security researchers will be able to streamline communication with MSRC case SPMs case managers, attach additional files, track case and bug bounty status all in the Researcher...

New High Impact Scenarios and Awards for the Azure Bounty Program

Microsoft is excited to announce new Azure Bounty Program awards up to $60,000 to encourage and reward vulnerability research focused on the highest potential impact to customer security. These increased awards are a part of our ongoing investment in partnership with the security research...

Concluding the Azure Sphere Security Research Challenge, Microsoft Awards $374,300 to Global Security Research Community

The Azure Sphere Security Research Challenge brought together 70 researchers from 21 countries to help secure Azure Sphere customers and expand Microsoft’s partnerships with the global IoT security research community. During the three-month Azure Sphere Security Research Challenge, researchers...

Advance Notification Service for the November 2014 Security Bulletin Release

Today, we provide advance notification for the release of 16 Security Bulletins. Five of these updates are rated Critical, nine are rated as Important, and two are rated Moderate in severity. These updates are for Microsoft Windows, Internet Explorer, Office, Exchange, .NET Framework, Internet...

A shared responsibility: Protecting customers through Coordinated Vulnerability Disclosure

In recent weeks several zero-day vulnerabilities have been publicly disclosed. The details of these vulnerabilities were not shared with Microsoft prior to release, and the disclosures put our customers at unnecessary risk...

Zero Day Quest: Join the largest hacking event with up to $5 million in total bounty awards

Last year, we announced the largest hacking event in history: Zero Day Quest, with up to $4 million in bounty awards. The response from the global security community was incredible and helped improve security for our customers and partners. This year, Zero Day Quest is back with even more potenti...

Mitigating NTLM Relay Attacks by Default

Introduction In February 2024, we released an update to Exchange Server which contained a security improvement referenced by CVE-2024-21410 that enabled Extended Protection for Authentication EPA by default for new and existing installs of Exchange 2019. While we’re currently unaware of any activ...

Microsoft Bounty Program Year in Review: $16.6M in Rewards

We are excited to announce that this year the Microsoft Bounty Program has awarded $16.6M in bounty awards to 343 security researchers from 55 countries, securing Microsoft customers in partnership with the Microsoft Security Response Center MSRC. Each year we identify over a thousand potential...

Faye’s Journey: From Security PM to Diversity Advocate at Microsoft

Faye, a veteran at Microsoft for 22 years, has had a career as varied as it is long. Her journey began in 2002 as the first desktop security Project Manager PM in Microsoft IT. From there, she transitioned into owning a deployment team that deployed to desktops and handled operations for Office’s...

レイヤー7の分散型サービス拒否 (DDoS) 攻撃に対するマイクロソフトの対応について

本ブログは、Microsoft Response to Layer 7 Distributed Denial of Service DDoS Attacks の抄訳版です。最新の情報は原文を参照してください。...

マイクロソフトのオンラインサービスにおける、脆弱性の深刻度分類の公開

本ブログは、Microsoft Vulnerability Severity Classification for Online Services Publication の抄訳版です。最新の情報は原文を参照してください。 マイク...

Azure Storage Keys、Azure Functions、Azure Role Based Access に関するベスト プラクティス

本ブログは、Best practices regarding Azure Storage Keys, Azure Functions, and Azure Role Based Access の抄訳版です。最新の情報は原文を参照してください。 概要 概...

Microsoft Investigation - Threat actor consent phishing campaign abusing the verified publisher process

Summary On December 15th, 2022, Microsoft became aware of a consent phishing campaign involving threat actors fraudulently impersonating legitimate companies when enrolling in the Microsoft Cloud Partner Program MCPP formerly known as Microsoft Partner Network MPN. The actor used fraudulent partn...

Top MSRC 2020 Q2 Security Researchers Announced – Congratulations!

We are excited to announce the top contributing researchers for the 2020 Second Quarter Q2! Congratulations to all the researchers who continue to rock the leaderboard, and a big thank you to everyone for your contribution to securing our customers and the ecosystem. The top three researchers of...

Calling for security research in Azure Sphere, now generally available

Today, Microsoft released Azure Sphere into General Availability GA. Azure Sphere’s mission is to empower every organization on the planet to connect and create secured and trustworthy IoT devices. Azure Sphere is an end-to-end solution for securely connecting existing equipment and for creating...

February 2020 security updates are available

We have released the February security updates to provide additional protections against malicious attackers. As a best practice, we encourage customers to turn on automatic updates. More information about this month’s security updates can be found in the Security Update Guide. The post February...

Building the Azure IoT Edge Security Daemon in Rust

Azure IoT Edge is an open source, cross platform software project from the Azure IoT team at Microsoft that seeks to solve the problem of managing distribution of compute to the edge of your on-premise network from the cloud. This post explains some of the rationale behind our choice of Rust as t...

BlueHat Shanghai 2019: Amplifying the power of defensive partnerships around the world

Earlier this week BlueHat Shanghai brought together security researchers and hundreds of cybersecurity professionals from China and across Asia to explore the latest topics in cybersecurity research. Including presentations from Qihoo 360, Baidu, Alibaba and the Chinese Academy of Sciences, BlueH...

Hyper-V Debugging Symbols Are Publicly Available

The security of Microsoft’s cloud services is a top priority for us. One of the technologies that is central to cloud security is Microsoft Hyper-V which we use to isolate tenants from one another in the cloud. Given the importance of this technology, Microsoft has made and continues to make...

February 2017 security update release

UPDATE: 2/15/17: We will deliver updates as part of the planned March Update Tuesday, March 14, 2017. Our top priority is to provide the best possible experience for customers in maintaining and protecting their systems. This month, we discovered a last minute issue that could impact some custome...

Understanding CVE-2025-55315: What CISOs, security engineers, and sysadmins should know

On October 14, 2025, Microsoft released a security update addressingCVE-2025-55315, a vulnerability in ASP.NET Core that allows HTTP request smuggling. While request smuggling is a known technique, this security update addresses a scenario with a high CVSS score to help encourage mitigation actio...

Congratulations to the Top MSRC 2025 Q1 Security Researchers!

Congratulations to all the researchers recognized in this quarter’s Microsoft Researcher Recognition Program leaderboard! Thank you to everyone for your hard work and continued partnership to secure customers. The top three researchers of the 2025 Q1 Security Researcher Leaderboard are 0x140ce,...

Congratulations to the Top MSRC 2024 Q1 Security Researchers!

Congratulations to all the researchers recognized in this quarter’s Microsoft Researcher Recognition Program leaderboard! Thank you to everyone for your hard work and continued partnership to secure customers. The top three researchers of the 2024 Q1 Security Researcher Leaderboard are Yuki Chen,...

Microsoft guidance regarding credentials leaked to GitHub Actions Logs through Azure CLI

Summary The Microsoft Security Response Center MSRC was made aware of a vulnerability where Azure Command-Line Interface CLI could expose sensitive information, including credentials, through GitHub Actions logs. The researcher, from Palo Alto Networks Prisma Cloud, found that Azure CLI commands...

Microsoft Vulnerability Severity Classification for Online Services Publication

The Microsoft Security Response Center MSRC is always looking for ways to provide clarity and transparency around how we assess the impact of vulnerabilities reported in our products and services. We have published a new Microsoft Vulnerability Severity Classification for Online Services to provi...

2023 年 4 月のセキュリティ更新プログラム (月例)

2023 年 4 月 11 日 米国時間 、マイクロソフトは、マイクロソフト製品に影響する脆弱性を修正するために、セキ...

First steps in CHERIoT Security Research

At Microsoft, we invest a lot of time researching and investigating possibilities in our journey to memory safety. Because the massive majority of existing codebases are written in unsafe programming languages, the task of protecting legacy code is very important. Hardware solutions are an...

Congratulations to the Top MSRC 2022 Q4 Security Researchers!

Congratulations to all the researchers recognized in this quarter’s Microsoft Researcher Recognition Program leaderboard! Thank you to everyone for your hard work and continued partnership to secure customers. The top three researchers of the 2022 Q4 Security Researcher Leaderboard are:...

Announcing the Microsoft Machine Learning Membership Inference Competition (MICO)

We’re excited to announce the launch of a new competition focusing on the security and privacy of machine learning ML systems. Machine learning has already become a key enabler in many products and services, and this trend is likely to continue. It is therefore critical to understand the security...

Announcing the Microsoft Machine Learning Membership Inference Competition (MICO)

We’re excited to announce the launch of a new competition focusing on the security and privacy of machine learning ML systems. Machine learning has already become a key enabler in many products and services, and this trend is likely to continue. It is therefore critical to understand the security...

Hunting for Cobalt Strike: Mining and plotting for fun and profit

Introduction Cobalt Strike is a commercial Command and Control framework built by Helpsystems. You can find out more about Cobalt Strike on the MITRE ATT&CK page. But it can also be used by real adversaries. In this post we describe how to use RiskIQ and other Microsoft technologies to see if you...

Randomizing the KUSER_SHARED_DATA Structure on Windows

Windows 10 made a lot of improvements in Kernel Address Space Layout Randomization KASLR that increases the cost of exploitation, particularly for remote code execution exploits. Many kernel virtual address space VAS locations including kernel stacks, pools, system PTEs etc. are randomized. A...

Researcher Spotlight: Cyber Viking Nate Warfield is Here to Help

“There are few jobs where I can say, I make two billion people more secure on the internet every single day.” Childhood Look: Goth kid, all in black Current Look: Cyber Viking Childhood hobby: Head banging to Metallica, Marilyn Manson, and Guns N’ Roses Current hobby: n0x08 DJ’s Live events aroun...

2022 年 2 月のセキュリティ更新プログラム (月例)

2022 年 2 月 8 日（米国時間）、マイクロソフトは、マイクロソフト製品に影響する脆弱性を修正するために、セキ...

Congratulations to the Top MSRC 2021 Q4 Security Researchers!

Congratulations to all the researchers recognized in this quarter’s Microsoft Researcher Recognition Program leaderboard! Thank you to everyone for your hard work and continued partnership to secure customers. The top three researchers of the 2021 Q4 Security Researcher Leaderboard are: rezer0dai...

Expanding the Microsoft Researcher Recognition Program

The Microsoft Researcher Recognition Program offers public thanks and recognition to security researchers who help protect our customers through discovering and sharing security vulnerabilities under Coordinated Vulnerability Disclosure. Today, we are expanding the program to recognize more...

Congratulations to the Top MSRC 2021 Q3 Security Researchers!

Congratulations to all the researchers recognized in this quarter’s MSRC Researcher Recognition Program leaderboard! Thank you to everyone for your hard work and continued partnership to secure customers. The top three researchers of the 2021 Q3 Security Researcher Leaderboard are: BugHunter010 8...

Congratulations to the MSRC’s 2020 Most Valuable Security Researchers

Today we announce our Most Valuable Security Researchers for 2020! The MSRC Researcher Recognition program is an integral aspect of recognizing the ongoing partnerships with our community of talented security researchers who report through Coordinated Vulnerability Disclosure CVD. These...

Updates to the Windows Insider Preview Bounty Program

Partnering with the research community is an important part of Microsoft’s holistic approach to defending against security threats. Bounty programs are one part of this partnership, designed to encourage and reward vulnerability research focused on the highest impact to customer security. The...

Time for day 2 of briefings at BlueHat Seattle!

We hope you enjoyed the first day of our BlueHat briefings and the Bytes of BlueHat reception in our glamping tent complete with toasted marshmallows. Yesterday, we learned a lot about how XboxOne hardware security has advanced the state of hardware security elsewhere, we heard some surprising...

Inside the MSRC – Anatomy of a SSIRP incident

This is the second in a series of blog posts that shares how the MSRC responds to elevated threats to customers through the Software and Services Incident Response Plan SSIRP. In our last blog post, we looked at the history of the Microsoft Security Response Center and SSIRP, and how Microsoft...

Vulnerability hunting with Semmle QL, part 1

Previously on this blog, we’ve talked about how MSRC automates the root cause analysis of vulnerabilities reported and found. After doing this, our next step is variant analysis: finding and investigating any variants of the vulnerability. It’s important that we find all such variants and patch...

DLL の植え付けの脆弱性のトリアージ

本記事は、Security Research & Defense のブログ “Triaging a DLL planting vulnerability” 2018 年 4 月...

Encapsulated PostScript (EPS) の脆弱性を利用した攻撃に対処するために団結する

本記事は、MSRC Team のブログ “Coming together to address Encapsulated PostScript EPS attacks” 2017 年 5 月 9 日 米国時間公開 を翻...

“The bugs pick you”: Inside Wouter’s security research journey

If you ask Wouter when his security journey began, he’ll take you back to a childhood in the Netherlands, tinkering with the 8086 PC his parents brought home when he was five or six. That early curiosity, fueled by racing games, trial-and-error exploration, and a tendency to pull things apart jus...

Microsoft Actions Following Attack by Nation State Actor Midnight Blizzard

The Microsoft security team detected a nation-state attack on our corporate systems on January 12, 2024, and immediately activated our response process to investigate, disrupt malicious activity, mitigate the attack, and deny the threat actor further access. Microsoft has identified the threat...

Congratulations to the Top MSRC 2023 Q3 Security Researchers!

Congratulations to all the researchers recognized in this quarter’s Microsoft Researcher Recognition Program leaderboard! Thank you to everyone for your hard work and continued partnership to secure customers. The top three researchers of the 2023 Q3 Security Researcher Leaderboard are Wei,...

Congratulations to the Top MSRC 2023 Q2 Security Researchers!

Congratulations to all the researchers recognized in this quarter’s Microsoft Researcher Recognition Program leaderboard! Thank you to everyone for your hard work and continued partnership to secure customers. The top three researchers of the 2023 Q2 Security Researcher Leaderboard are: Yuki Chen...