Category: Microsoft Security Response Center

postMessaged and Compromised

At Microsoft, securing the ecosystem means more than just fixing bugs—it means proactively hunting for variant classes, identifying systemic weaknesses, and working across teams to protect customers before attackers ever get the chance. This blog highlights one such effort: a…

Microsoft Bounty Program year in review: $17 million in rewards

We’re thrilled to share that this year, the Microsoft Bounty Program has distributed $17 million to 344 security researchers from 59 countries, the highest total bounty awarded in the program’s history. In close collaboration with the Microsoft Security Response Center (MSRC),…

.NET Bounty Program now offers up to $40,000 in awards

We’re excited to announce significant updates to the Microsoft .NET Bounty Program. These changes expand the program’s scope, simplify the award structure, and offer great incentives for security researchers. The .NET Bounty Program now offers awards up to $40,000 USD for vulnerabilities impacting the .NET and…

How Microsoft defends against indirect prompt injection attacks

Summary The growing adoption of large language models (LLMs) in enterprise workflows has introduced a new class of adversarial techniques: indirect prompt injection. Indirect prompt injection can be used against systems that leverage large language models (LLMs) to process untrusted…

Customer guidance for SharePoint vulnerability CVE-2025-53770

Summary Microsoft is aware of active attacks targeting on-premises SharePoint Server customers. The attacks are exploiting a variant of CVE-2025-49706. This vulnerability has been assigned CVE-2025-53770. SharePoint Online in Microsoft 365 is not impacted. A patch is currently not available for…

Congratulations to the MSRC 2025 Most Valuable Security Researchers!

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 excited to recognize this year’s 100 Most Valuable Researchers…

Congratulations to the top MSRC 2025 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 2025 Q2 Security Researcher Leaderboard are…

Rising star: Meet Dylan, MSRC’s youngest security researcher

At just 13 years old, Dylan became the youngest security researcher to collaborate with the Microsoft Security Response Center (MSRC). His journey into cybersecurity is inspiring—rooted in curiosity, resilience, and a deep desire to make a difference. Early beginnings: From…

RedirectionGuard: Mitigating unsafe junction traversal in Windows

As attackers continue to evolve, Microsoft is committed to staying ahead by not only responding to vulnerabilities, but also by anticipating and mitigating entire classes of threats. One such threat, filesystem redirection attacks, has been a persistent vector for privilege…

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…

Zero Day Quest 2025: $1.6 million awarded for vulnerability research

This month, the Microsoft Security Response Center recently welcomed some of the world’s most talented security researchers at Microsoft’s Zero Day Quest, the largest live hacking competition of its kind. The inaugural event challenged the security community to focus on…

Jailbreaking is (mostly) simpler than you think

Content warning: This blog post contains discussions of sensitive topics. These subjects may be distressing or triggering for some readers. Reader discretion is advised. Today, we are sharing insights on a simple, optimization-free jailbreak method called Context Compliance Attack (CCA),…

Scaling Dynamic Application Security Testing (DAST)

Table of Contents Introduction Why most enterprises have trouble scaling DAST Web endpoint discovery Automated OpenAPI Specification generation solutions that do scale (sort of) Authentication and authorization A scalable DAST solution Web endpoint discovery Authentication and authorization Authentication hook Authorization…

Congratulations to the Top MSRC 2024 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 2024 Q4 Security Researcher Leaderboard are…

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…

Announcing the Adaptive Prompt Injection Challenge (LLMail-Inject)

We are excited to introduce LLMail-Inject, a new challenge focused on evaluating state-of-the-art prompt injection defenses in a realistic simulated LLM-integrated email client. In this challenge, participants assume the role of an attacker who sends an email to a user.…

Securing AI and Cloud with the Zero Day Quest

Our security teams work around the clock to help protect every person and organization on the planet from security threats. We also know that security is a team sport, and that’s why we also partner with the global security community…

Congratulations to the Top MSRC 2024 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 2024 Q3 Security Researcher Leaderboard are…

Announcing the BlueHat 2024 Sessions

34 sessions from 54 presenters representing 20 organizations! We are thrilled to reveal the lineup of speakers and presentations for the 23rd BlueHat Security Conference, in Redmond WA from Oct 29-30. This year’s conference continues the BlueHat ethos and Secure Future…

Announcing BlueHat 2024: Call for Papers now open

The 23rd edition of Microsoft’s BlueHat security conference will be hosted by the Microsoft Security Response Center (MSRC) at the Redmond, WA corporate campus, October 29 and 30, 2024. BlueHat brings together security researchers and responders from both inside and outside…

Congratulations to the MSRC 2024 Most Valuable Security Researchers!

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 excited to recognize this year’s 100 Most Valuable Researchers…

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…

Introducing the MSRC Researcher Resource Center

Microsoft partners with the global security researcher community to surface and report security vulnerabilities to protect all users of Microsoft products and services. Researcher submissions help us address immediate threats while also identifying trends and insights to holistically improve the…

Congratulations to the Top MSRC 2024 Q2 Security Researchers!

Congratulations to all the researchers recognized in this quarter’s [Microsoft Researcher Recognition Program](https://www.microsoft.com/en-us/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 2024 Q2 Security Researcher Leaderboard are…

Announcing the CVRF API 3.0 upgrade

At the Microsoft Security Response Center, we are committed to continuously improving the security and performance of our services to meet the evolving needs of our customers. We are excited to announce the rollout of the latest version of our…

What’s new in the MSRC Report Abuse Portal and API

The Microsoft Security Response Center (MSRC) has always been at the forefront of addressing cyber threats, privacy issues, and abuse arising from Microsoft Online Services. Building on our commitment, we have introduced several key updates to the Report Abuse Portal…

Toward greater transparency: Unveiling Cloud Service CVEs

Welcome to the second installment in our series on transparency at the Microsoft Security Response Center (MSRC). In this ongoing discussion, we discuss our commitment to provide comprehensive vulnerability information to our customers. At MSRC, our mission is to protect our…

Mitigating SSRF Vulnerabilities Impacting Azure Machine Learning

Summary On May 9, 2024, Microsoft successfully addressed multiple vulnerabilities within the Azure Machine Learning (AML) service, which were initially discovered by security research firms Wiz and Tenable. These vulnerabilities, which included Server-Side Request Forgeries (SSRF) and a path traversal…

Improved Guidance for Azure Network Service Tags

Summary Microsoft Security Response Center (MSRC) was notified in January 2024 by our industry partner, Tenable Inc., about the potential for cross-tenant access to web resources using the service tags feature. Microsoft acknowledged that Tenable provided a valuable contribution to…

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…

Congratulations to the Top MSRC 2023 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 2023 Q4 Security Researcher Leaderboard are…

BlueHat India Call for Papers is Now Open!

You asked for it and it’s finally here! The inaugural BlueHat India conference will be held April 18-19, 2024, in Hyderabad, India! This intimate conference will bring together a unique blend of security researchers and responders, who come together as peers…

Microsoft addresses App Installer abuse

Summary In recent months, Microsoft Threat Intelligence has observed threat actors leveraging social engineering and phishing techniques to target Windows OS users and utilizing the ms-appinstaller URI scheme. We have addressed and mitigated this malicious activity by turning off ms-appinstaller…

Azure Serial Console Attack and Defense – Part 2

This is the second installment of the Azure Serial Console blog, which provides insights to improve defenders’ preparedness when investigating Azure Serial Console activity on Azure Linux virtual machines. While the first blog post discussed various tracing activities, such as…

Microsoft Mitigates Three Vulnerabilities in Azure HDInsight

Summary Summary Microsoft recently remediated one Denial of Service and two Escalation of Privilege vulnerabilities affecting third party components of Azure HDInsight. Access to the target cluster as an authenticated user was a prerequisite for exploitation in all three cases.…

Introducing the Microsoft Defender Bounty Program

We are excited to announce the new Microsoft Defender Bounty Program with awards of up to $20,000 USD. The Microsoft Defender brand encompasses a variety of products and services designed to enhance the security of the Microsoft customer experience. The…

Reflecting on 20 years of Patch Tuesday

This year is a landmark moment for Microsoft as we observe the 20th anniversary of Patch Tuesday updates, an initiative that has become a cornerstone of the IT world’s approach to cybersecurity. Originating from the Trustworthy Computing memo by Bill…

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…

Cybersecurity Awareness Month 2023: Elevating Security Together

As the 20th anniversary of Cybersecurity Awareness Month begins, I find myself reflecting on the strides made since its inception. The journey to enhance and improve cybersecurity is ongoing and extends beyond October. It’s not merely a technological challenge; it is…

Journey Down Under: How Rocco Became Australia’s Premier Hacker

Fun facts about Rocco: Microsoft MVR: Rocco is a 2023 Microsoft Most Valuable Researcher. Fitness fanatic: Inspired by old-school body building and countless hours of chopping and carrying wood in the mountains during his youth, Rocco remains a fitness enthusiast,…

Congratulations to the MSRC 2023 Most Valuable Security Researchers!

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 excited to recognize this year’s top 100 Most Valuable…

BlueHat October 2023 Call for Papers is Now Open!

As you may have seen on social media, the next BlueHat conference will be October 11 – 12, 2023, on Microsoft’s Redmond campus in Washington state, USA. The Call for Papers (CFP) is now open through August 18, 2023. The…

What to Expect When Reporting Vulnerabilities to Microsoft

At the Microsoft Security Response Center (MSRC), our mission is to protect our customers, communities, and Microsoft from current and emerging threats to security and privacy. One of the ways we do this is by working with security researchers to…

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:…

Azure AD アプリケーションにおける特権昇格の潜在的なリスクについて

本ブログは、Potential Risk of Privilege Escalation in Azure AD Applications 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 This article has been indexed from Microsoft Security Response Center Read the original article: Azure AD アプリケーションにおける特権昇格の潜在的なリスクについて

Potential Risk of Privilege Escalation in Azure AD Applications

Summary Summary Microsoft has developed mitigations for an insecure anti-pattern used in Azure AD (AAD) applications highlighted by Descope, and reported to Microsoft, where use of the email claim from access tokens for authorization can lead to an escalation of privilege. An…

Microsoft Response to Layer 7 Distributed Denial of Service (DDoS) Attacks

Summary Summary Beginning in early June 2023, Microsoft identified surges in traffic against some services that temporarily impacted availability. Microsoft promptly opened an investigation and subsequently began tracking ongoing DDoS activity by the threat actor that Microsoft tracks as Storm-1359.…

2023 年 6 月のセキュリティ更新プログラム (月例)

2023 年 6 月 13 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 This article has been indexed from Microsoft Security Response Center Read the original article: 2023 年 6 月のセキュリティ更新プログラム (月例)

Hey Yara, find some vulnerabilities

Intro Intro Finding vulnerabilities in software is no easy task by itself. Doing this at cloud scale is very challenging to perform manually, and we use tools to help us identify patterns or vulnerability signatures. Yara is one of those tools. Yara…

Announcing The BlueHat Podcast: Listen and Subscribe Now!

Available today on all major podcast platforms is The BlueHat Podcast, a new series of security research focused conversations, continuing the themes from the BlueHat 2023 conference (session recordings available to watch here). Since 2005, BlueHat has been where the…

2023 年 5 月のセキュリティ更新プログラム (月例)

2023 年 5 月 9 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 This article has been indexed from Microsoft Security Response Center Read the original article: 2023 年 5 月のセキュリティ更新プログラム (月例)

Congratulations to the Top MSRC 2023 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 2023 Q1 Security Researcher Leaderboard are: Kai…

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 This article has been indexed from Microsoft Security Response Center Read the original article: 2023 年 4 月のセキュリティ更新プログラム (月例)

Azure ADを使用するマルチテナント アプリケーションの承認に関する構成ミスの可能性に関するガイダンス

本ブログは、Guidance on Potential Misconfiguration of Authorization of Multi-Tenant Applications that use Azure AD の抄訳版です。最新の情報は原文を参照してください This article has been indexed from Microsoft Security Response Center Read the original article: Azure ADを使用するマルチテナント アプリケーションの承認に関する構成ミスの可能性に関するガイダンス

Microsoft Mitigates Outlook Elevation of Privilege Vulnerability

Summary Summary Microsoft Threat Intelligence discovered limited, targeted abuse of a vulnerability in Microsoft Outlook for Windows that allows for new technology LAN manager (NTLM) credential theft. Microsoft has released CVE-2023-23397 to address the critical elevation of privilege (EoP) vulnerability…

Configuring host-level audit logging for AKS VMSS

This blog post runs you through how to enable and configure Linux audit logging on your Azure Kubernetes Service (AKS) Virtual Machine Scale Set (VMSS) using the Linux auditing subsystem, also known as auditd. Warning The information provided below is…

Azure Kubernetes Service (AKS) Threat Hunting

As more businesses shift away from running workloads on dedicated virtual machines to running them inside containers using workload orchestrators like Kubernetes, adversaries have become more interested in them as targets. Moreover, the benefits Kubernetes provides for managing workloads are…

First steps in CHERIoT Security Research

First steps in CHERIoT Security Research 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…

2023 年 2 月のセキュリティ更新プログラム (月例)

2023 年 2 月 14 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 This article has been indexed from Microsoft Security Response Center Read the original article: 2023 年 2 月のセキュリティ更新プログラム (月例)

New MSRC Blog Site

We are excited to announce the release of the new Microsoft Security Response Center (MSRC) blog site. Please visit msrc.microsoft.com/blog/starting February 9th, 2023, for all past and future MSRC blog content.  In addition to the new URL, we have refreshed…

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:…

Microsoft resolves four SSRF vulnerabilities in Azure cloud services

Summary  Microsoft recently fixed a set of Server-Side Request Forgery (SSRF) vulnerabilities in four Azure services (Azure API Management, Azure Functions, Azure Machine Learning, and Azure Digital Twins) reported by Orca Security. These SSRF vulnerabilities were determined to be low…

Publishing CBL-Mariner CVEs on the Security Update Guide CVRF API

Microsoft is pleased to announce that beginning January 11, 2023, we will publish CBL-Mariner CVEs in the Security Update Guide (SUG) Common Vulnerability Reporting Framework (CVRF) API. CBL-Mariner is a Linux distribution built by Microsoft to power Azure’s cloud and…