Windows Security

We’re excited to announce the top contributing researchers for the 2021 First Quarter (Q1)! Congratulations to all the researchers recognized in this quarter’s leaderboard and thank you to everyone who continues to help secure our customers and theView the full article

Update August 25, 2021: Microsoft strongly recommends that you update your servers with the most recent security updates available. CVE-2021-34473 (ProxyShell) CVE-2021-34523 (ProxyShell) CVE-2021-33766 Today is Update Tuesday – our commitment to provide a predictable monthly schedule to release updates and provide the latest protection to our customers. Update Tuesday is a monthly cycle when Microsoft releases patches for vulnerabilities that we have found proactively or that have been disclosed to us through our security partnerships under a coordinated vulnerability disclosure.View the full article

Partnering with the security research community is an important part of Microsoft’s holistic approach to defending against security threats. As much of the world has shifted to working from home in the last year, Microsoft Teams has enabled people to stay connected, organized, and collaborate remotely. Microsoft and security researchers across the planet continue to partner to help secure customers and the technologies we use for remote collaboration.View the full article

This guidance will help customers address threats taking advantage of the recently disclosed Microsoft Exchange Server on-premises vulnerabilities CVE-2021-26855, CVE-2021-26858, CVE-2021-26857, and CVE-2021-27065, which are being exploited. We strongly urge customers to immediately update systems. Failing to address these vulnerabilities can result in compromise of your on-premises Exchange Server and, potentially, other parts of your internal network.View the full article

We have been actively working with customers through our customer support teams, third-party hosters, and partner network to help them secure their environments and respond to associated threats from the recent Exchange Server on-premises attacks. Based on these engagements we realized that there was a need for a simple, easy to use, automated solution that would meet the needs of customers using both current and out-of-support versions of on-premises Exchange Server.View the full article

Update March 15, 2021: If you have not yet patched, and have not applied the mitigations referenced below, a one-click tool, the Exchange On-premises Mitigation Tool is now our recommended path to mitigate until you can patch. Microsoft previously blogged our strong recommendation that customers upgrade their on-premises Exchange environments to the latest supported version.View the full article

The Notice of Copyright or Trademark Infringement Portal has helped protect Microsoft’s users and customers from intellectual property infringement across online services like Microsoft Azure, Office, Outlook, Skype, Stream, Microsoft News, Sway, Hotmail, NuGet, and Yammer. Microsoft’s response to claims of intellectual property infringement is driven by the reports you send us.View the full article

On March 2nd, we released several security updates for Microsoft Exchange Server to address vulnerabilities that are being used in ongoing attacks. Due to the critical nature of these vulnerabilities, we recommend that customers protect their organizations by applying the patches immediately to affected systems. The vulnerabilities affect Exchange Server versions 2013, 2016, and 2019, while Exchange Server 2010 is also being updated for defense-in-depth purposes.View the full article

We believe the Solorigate incident is an opportunity to work with the community, to share information, strengthen defenses and respond to attacks. We have now completed our internal investigation into the activity of the actor and want to share our findings, which confirm that we found no evidence of access to production services or customer data.View the full article

Wondering how to get into the 2021 MSRC Most Valuable Security Researcher list and get recognized during the Black Hat USA this August? Read on to learn more about the different paths you can take to get into the top researcher tiers. The MSRC Most Valuable Security Researcher (MVR) and MSRC Contributor are tiers in the Researcher Recognition Program which annually recognize researchers for impactful contributions, considering report impact, accuracy and volume.View the full article

Today Microsoft released a set of fixes affecting Windows TCP/IP implementation that include two Critical Remote Code Execution (RCE) vulnerabilities (CVE-2021-24074, CVE-2021-24094) and an Important Denial of Service (DoS) vulnerability (CVE-2021-24086). The two RCE vulnerabilities are complex which make it difficult to create functional exploits, so they are not likely in the short term.View the full article

Based on user feedback we have simplified programmatic access to the security update data by removing the authentication and API-Key requirements when using the CVRF API. You will no longer have to log in to obtain a personal API key to access the data. We’re happy to make this valuable public information more freely available and accessible.View the full article

The Report Abuse (CERT) Portal and Report Abuse API have played a significant role in MSRC’s response to suspected cyberattacks, privacy issues, and abuse originating from Microsoft Online Services. With the contributions from our wonderful community of reporters, we continue to gain insightful perspectives into the various types of attacks that threaten our online services, our cloud, and our customers.View the full article

We’re excited to announce the top contributing researchers for the 2020 Fourth Quarter (Q4)! Congratulations to all of the researchers who made this quarter’s leaderboard and a huge thank you to everyone who continues to help secure our customers and the ecosystem. The top three researchers of the 2020 Q4 Security Researcher Leaderboard are: Cameron Vincent (2065 points) , Yuki Chen (1535 points) , and Suresh C (862 points).View the full article

Microsoft addressed a Critical RCE vulnerability affecting the Netlogon protocol (CVE-2020-1472) on August 11, 2020. We are reminding our customers that beginning with the February 9, 2021 Security Update release we will be enabling Domain Controller enforcement mode by default. This will block vulnerable connections from non-compliant devices. DC enforcement mode requires that all Windows and non-Windows devices use secure RPC with Netlogon secure channel unless customers have explicitly allowed the account to be vulnerable by adding an exception for the non-compliant device.View the full article

Hi Folks, This month we are introducing a new data element for each CVE in the Security Update Guide, called Assigning CNA. First let me back up a bit and give some information about the CVE program. The purpose of a CVE is to uniquely identify a cybersecurity vulnerability. The CVE program was started back in 1999 and is funded by the US federal government, currently out of the Cybersecurity and Infrastructure Security Agency (CISA).View the full article

As we said in our recent blog, we believe the Solorigate incident is an opportunity to work together in important ways, to share information, strengthen defenses and respond to attacks. Like other SolarWinds customers, we have been actively looking for indicators of the Solorigate actor and want to share an update from our ongoing internal investigation.View the full article

UPDATE: 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. Microsoft previously used ‘Solorigate’ as the primary designation for the actor, but moving forward, we want to place appropriate focus on the actors behind the sophisticated attacks, rather than one of the examples of malware used by the actors.View the full article

Note: we are updating as the investigation continues. Revision history listed at the bottom. This post contains technical details about the methods of the actor we believe was involved in Recent Nation-State Cyber Attacks, with the goal to enable the broader security community to hunt for activity in their networks and contribute to a shared defense against this sophisticated threat actor.View the full article

Hi Folks, We want to continue to highlight changes we’ve made to our Security Update Guide. We have received a lot of feedback, much of which has been very positive. We acknowledge there have been some stability problems and we are actively working through reports of older browsers not being able to run the new application.View the full article

With the launch of the new version of the Security Update Guide, Microsoft is demonstrating its commitment to industry standards by describing the vulnerabilities with the Common Vulnerability Scoring System (CVSS). This is a precise method that describes the vulnerability with attributes such as the attack vector, the complexity of the attack, whether an adversary needs certain privileges, etc.View the full article

Microsoft has received a small number of reports from customers and others about continued activity exploiting a vulnerability affecting the Netlogon protocol (CVE-2020-1472) which was previously addressed in security updates starting on August 11, 2020. If the original guidance is not applied, the vulnerability could allow an attacker to spoof a domain controller account that could be used to steal domain credentials and take over the domain.View the full article

Following the MSRC’s 2020 Most Valuable Security Researchers announced during this year’s Black Hat, we’re excited to announce the top contributing researchers for the 2020 Third Quarter (Q3)! The top three researchers of the 2020 Q3View the full article

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 surfaced 20 Critical or Important severity security vulnerabilities, with Microsoft awarding $374,300 in bounty awards for 16 bounty eligible reports.View the full article

We’re excited to announce a significant update to the Security Update Guide, our one-stop site for information about all security updates provided by Microsoft. This new version will provide a more intuitive user experience to help protect our customers regardless of what Microsoft products or services they use in their environment.View the full article