Today, Microsoft Threat Intelligence Center is excited to announce the release of RIFT, a tool designed to assist malware analysts automate the identification of attacker-written code within Rust binaries. Known for its efficiency, type safety, and robust memory safety, Rust has increasingly become a tool for creating malware, especially among financially motivated groups and nation-state entities. This shift has introduced new challenges for malware analysts as the unique characteristics of Rust binaries make static analysis more complex.
One of the primary challenges in reverse engineering malware developed with Rust lies in its layers of abstraction added through features such as memory safety and concurrency handling, making it more challenging to identify the behavior and intent of the malware. Compared to traditional languages, Rust binaries are often larger and more complex due to the incorporation of extensive library code. Consequently, reverse engineers must undertake the demanding task of distinguishing attacker-written code from standard library code, necessitating advanced expertise and specialized tools.
To address these pressing challenges, Microsoft Threat Intelligence Center has developed RIFT. RIFT underscores the growing need for specialized tools as cyber threat actors continue to leverage Rust’s features to evade detection and complicate analysis. The adoption of Rust by threat actors is a stark reminder of the ever-changing tactics employed in the cyber domain, and the increasing sophistication required to combat these threats effectively. In this blog post, we explore how threat actors are increasingly adopting Rust for malware development due to its versatility and how RIFT can be used to combat this threat by enhancing the efficiency and accuracy of Rust-based malware analysis.
An ongoing phishing campaign abuses a little‑known feature in Microsoft 365 called "Direct Send" to evade detection by email security and steal credentials.
Direct Send is a Microsoft 365 feature that allows on‑premises devices, applications, or cloud services to send emails through a tenant's smart host as if they originated from the organization's domain. It’s designed for use by printers, scanners, and other devices that need to send messages on behalf of the company.
However, the feature is a known security risk, as it doesn't require any authentication, allowing remote users to send internal‑looking emails from the company's domain.
Microsoft recommends that only advanced customers utilize the feature, as its safety depends on whether Microsoft 365 is configured correctly and the smart host is properly locked down..
"We recommend Direct Send only for advanced customers willing to take on the responsibilities of email server admins," explains Microsoft.
"You need to be familiar with setting up and following best practices for sending email over the internet. When correctly configured and managed, Direct Send is a secure and viable option. But customers run the risk of misconfiguration that disrupts mail flow or threatens the security of their communication."
The company has shared ways to disable the feature, which are explained later in the article, and says they are working on a way to deprecate the feature.
Microsoft announced it will expand the list of blocked attachments in Outlook Web and the new Outlook for Windows starting next month.
Microsoft announced it will expand the list of blocked attachments in Outlook Web and the new Outlook for Windows starting next month.
The company said on Monday in a Microsoft 365 Message Center update that Outlook will block .library-ms and .search-ms file types beginning in July.
"As part of our ongoing efforts to enhance security in Outlook Web and the New Outlook for Windows, we're updating the default list of blocked file types in OwaMailboxPolicy," Microsoft said. "Starting in early July 2025, the [.library-ms and .search-ms] file types will be added to the BlockedFileTypes list."
As AI and digital technologies advance, the European cyber threat landscape continues to evolve, presenting new challenges that require stronger partnerships and enhanced solutions. Ransomware groups and state-sponsored actors from Russia, China, Iran, and North Korea continue to grow in scope and sophistication, and European cyber protection cannot afford to stand still.
That is why, today, in Berlin, we are announcing a new Microsoft initiative to expand our longstanding work to help defend Europe’s cybersecurity. Implementing one of the five European Digital Commitments I shared in Brussels five weeks ago, we are launching a new European Security Program that adds to the company’s longstanding global Government Security Program.
This new program expands the geographic reach of our existing work and adds new elements that will become critical to Europe’s protection. It puts AI at the center of our work as a tool to protect traditional cybersecurity needs and strengthens our protection of digital and AI infrastructure.
We are launching the European Security Program with three new elements:
Microsoft and CrowdStrike are teaming up to create alignment across our individual threat actor taxonomies to help security professionals connect insights faster.
In today’s cyberthreat landscape, even seconds of delay can mean the difference between stopping a cyberattack or falling victim to ransomware. One major cause of delayed response is understanding threat actor attribution, which is often slowed by inaccurate or incomplete data as well as inconsistencies in naming across platforms. This, in turn, can reduce confidence, complicate analysis, and delay response. As outlined in the National Institute of Standards and Technology’s (NIST) guidance on threat sharing (SP 800-1501), aligning how we describe and categorize cyberthreats can improve understanding, coordination, and overall security posture.
That’s why we are excited to announce that Microsoft and CrowdStrike are teaming up to create alignment across our individual threat actor taxonomies. By mapping where our knowledge of these actors align, we will provide security professionals with the ability to connect insights faster and make decisions with greater confidence.
Read about Microsoft and Crowdstrike’s joint threat actor taxonomy
Names are how we make sense of the threat landscape and organize insights into known or likely cyberattacker behaviors. At Microsoft, we’ve published our own threat actor naming taxonomy to help researchers and defenders identify, share, and act on our threat intelligence, which is informed by the 84 trillion threat signals that we process daily. But the same actor that Microsoft refers to as Midnight Blizzard might be referred to as Cozy Bear, APT29, or UNC2452 by another vendor. Our mutual customers are always looking for clarity. Aligning the known commonalities among these actor names directly with peers helps to provide greater clarity and gives defenders a clearer path to action.
Introducing a collaborative reference guide to threat actors
Microsoft and CrowdStrike are publishing the first version of our joint threat actor mapping. It includes:
A list of common actors tracked by Microsoft and CrowdStrike mapped by their respective taxonomies.
Corresponding aliases from each group’s taxonomy.
This reference guide serves as a starting point, a way to translate across naming systems so defenders can work faster and more efficiently, especially in environments where insights from multiple vendors are in play. This reference guide helps to:
Improve confidence in threat actor identification.
Streamline correlation across platforms and reports.
Accelerate defender action in the face of active cyberthreats.
This effort is not about creating a single naming standard. Rather, it’s meant to help our customers and the broader security community align intelligence more easily, respond faster, and stay ahead of threat actors.
Microsoft Threat Intelligence has discovered a cluster of worldwide cloud abuse activity conducted by a threat actor we track as Void Blizzard, who we assess with high confidence is Russia-affiliated and has been active since at least April 2024. Void Blizzard’s cyberespionage operations tend to be highly targeted at specific organizations of interest to Russia, including in government, defense, transportation, media, non-governmental organizations (NGOs), and healthcare sectors primarily in Europe and North America.
Microsoft’s head of security for AI, Neta Haiby, accidentally revealed confidential messages about Walmart’s use of Microsoft’s AI tools during a Build talk that was disrupted by protesters.
The Build livestream was muted and the camera pointed down, but the session resumed moments later after the protesters were escorted out. In the aftermath, Haiby then accidentally switched to Microsoft Teams while sharing her screen, revealing confidential internal messages about Walmart’s upcoming use of Microsoft’s Entra and AI gateway services.
Haiby was co-hosting a Build session on best security practices for AI, alongside Sarah Bird, Microsoft’s head of responsible AI, when two former Microsoft employees disrupted the talk to protest against the company’s cloud contracts with the Israeli government.
“Sarah, you are whitewashing the crimes of Microsoft in Palestine, how dare you talk about responsible AI when Microsoft is fueling the genocide in Palestine,” shouted Hossam Nasr, an organizer with the protest group No Azure for Apartheid, and a former Microsoft employee who was fired for holding a vigil outside Microsoft’s headquarters for Palestinians killed in Gaza.
Walmart is one of Microsoft’s biggest corporate customers, and already uses the company’s Azure OpenAI service for some of its AI work. “Walmart is ready to rock and roll with Entra Web and AI Gateway,” says one of Microsoft’s cloud solution architects in the Teams messages. The chat session also quoted a Walmart AI engineer, saying: “Microsoft is WAY ahead of Google with AI security. We are excited to go down this path with you.”
La Digital Crimes Unit (DCU) de Microsoft, en collaboration avec des partenaires internationaux, s’attaque à l’un des principaux outils utilisés pour dérober massivement des données sensibles, qu’elles soient personnelles ou professionnelles, à des fines cybercriminelles. Le mardi 13 mai, la DCU de Microsoft a engagé une action en justice contre Lumma Stealer (« Lumma »), un malware spécialisé dans le vol d’informations, largement utilisé par des centaines d’acteurs de la menace cyber. Lumma vole des mots de passe, des cartes de crédit, des comptes bancaires et des portefeuilles de cryptomonnaies. Cet outil a permis à des criminels de bloquer des établissements scolaires afin de récupérer une rançon, de vider des comptes bancaires et de perturber des services essentiels.
Grâce à une décision de justice rendue par le tribunal fédéral du district nord de la Géorgie, la Digital Crimes Unit (DCU) de Microsoft a procédé à la saisie et à la mise hors ligne d’environ 2 300 domaines malveillants, qui constituaient l’infrastructure centrale de Lumma. Parallèlement, le département de la Justice américain (DOJ) a démantelé la structure de commande principale du malware et perturbé les places de marché où l’outil était vendu à d’autres cybercriminels. Europol, via son Centre européen de lutte contre la cybercriminalité (EC3), ainsi que le Centre de lutte contre la cybercriminalité du Japon (JC3), ont contribué à la suspension de l’infrastructure locale de Lumma.
The International Criminal Court ’s chief prosecutor has lost access to his email, and his bank accounts have been frozen.
The Hague-based court’s American staffers have been told that if they travel to the U.S. they risk arrest.
Some nongovernmental organizations have stopped working with the ICC and the leaders of one won’t even reply to emails from court officials.
Those are just some of the hurdles facing court staff since U.S. President Donald Trump in February slapped sanctions on its chief prosecutor, Karim Khan, according to interviews with current and former ICC officials, international lawyers and human rights advocates.
The sanctions will “prevent victims from getting access to justice,” said Liz Evenson, international justice director at Human Rights Watch.
Trump sanctioned the court after a panel of ICC judges in November issued arrest warrants for Israeli Prime Minister Benjamin Netanyahu and his former defense minister, Yoav Gallant.
Judges found there was reason to believe that the pair may have committed war crimes by restricting humanitarian aid and intentionally targeting civilians in Israel’s campaign against Hamas in Gaza — charges Israeli officials deny.
One reason the the court has been hamstrung is that it relies heavily on contractors and non-governmental organizations. Those businesses and groups have curtailed work on behalf of the court because they were concerned about being targeted by U.S. authorities, according to current and former ICC staffers.
Microsoft, for example, cancelled Khan’s email address, forcing the prosecutor to move to Proton Mail, a Swiss email provider, ICC staffers said. His bank accounts in his home country of the U.K. have been blocked.
Microsoft did not respond to a request for comment.
Staffers at an NGO that plays an integral role in the court’s efforts to gather evidence and find witnesses said the group has transferred money out of U.S. bank accounts because they fear it might be seized by the Trump administration.
Overview: Check Point researchers have identified a new phishing campaign that exploits Microsoft’s “Dynamics 365 Customer Voice,” a customer relationship
Overview:
Check Point researchers have identified a new phishing campaign that exploits Microsoft’s “Dynamics 365 Customer Voice,” a customer relationship management software product. It’s often used to record customer calls, monitor customer reviews, share surveys and track feedback.
Microsoft 365 is used by over 2 million organizations worldwide. At least 500,000 organizations use Dynamics 365 Customer Voice, including 97% of Fortune 500 companies.
In this campaign, cyber criminals send business files and invoices from compromised accounts, and include fake Dynamics 365 Customer Voice links. The email configuration looks legitimate and easily tricks email recipients into taking the bait.
As part of this campaign, cyber criminals have deployed over 3,370 emails, with content reaching employees of over 350 organizations, the majority of which are American. More than a million different mailboxes were targeted.
Affected entities include well-established community betterment groups, colleges and universities, news outlets, a prominent health information group, and organizations that promote arts and culture, among others.
Researchers say the behavior amounts to a persistent backdoor.
rom the department of head scratches comes this counterintuitive news: Microsoft says it has no plans to change a remote login protocol in Windows that allows people to log in to machines using passwords that have been revoked.
Password changes are among the first steps people should take in the event that a password has been leaked or an account has been compromised. People expect that once they've taken this step, none of the devices that relied on the password can be accessed.
The Remote Desktop Protocol—the proprietary mechanism built into Windows for allowing a remote user to log in to and control a machine as if they were directly in front of it—however, will in many cases continue trusting a password even after a user has changed it. Microsoft says the behavior is a design decision to ensure users never get locked out.
Independent security researcher Daniel Wade reported the behavior earlier this month to the Microsoft Security Response Center. In the report, he provided step-by-step instructions for reproducing the behavior. He went on to warn that the design defies nearly universal expectations that once a password has been changed, it can no longer give access to any devices or accounts associated with it.
Microsoft synchronization capabilities for managing identities in hybrid environments are not without their risks. In this blog, Tenable Research explores how potential weaknesses in these synchronization options can be exploited.
Synchronizing identity accounts between Microsoft Active Directory (AD) and Entra ID is important for user experience, as it seamlessly synchronizes user identities, credentials and groups between on-premises and cloud-based systems. At the same time, Tenable Research shows the following synchronization options can introduce cybersecurity risk that extend beyond hybrid tenants:
the already known Directory Synchronization Accounts Entra role
the new On Premises Directory Sync Account Entra role
the new Microsoft Entra AD Synchronization Service application
In 2024, Microsoft introduced two new security hardening measures for hybrid Entra ID synchronization. However, despite these improvements, both the Directory Synchronization Accounts and the new On Premises Directory Sync Account roles retain access to critical synchronization APIs. Moreover, the new 'Microsoft Entra AD Synchronization Service' application exposes the privileged ADSynchronization.ReadWrite.All permission, introducing another potential attack path that security teams must watch closely.
In this technical blog, we break down the changes Microsoft made to each of its synchronization options, explore where new risks were introduced and provide guidance on how Tenable Identity Exposure can help you monitor and secure your hybrid synchronization environment.
Microsoft security chief Charlie Bell says the SFI’s 28 objectives are “near completion” and that 11 others have made “significant progress.”
Microsoft, touting what it calls “the largest cybersecurity engineering project in history,” says it has moved every Microsoft Account and Entra ID token‑signing key into hardware security modules or Azure confidential VMs with automatic rotation, an overhaul meant to block the key‑theft tactic that fueled an embarrassing nation‑state breach at Redmond.
Just 18 months after rolling out a Secure Future Initiative in response to the hack and a scathing US government report that followed, Microsoft security chief Charlie Bell said five of the program’s 28 objectives are “near completion” and that 11 others have made “significant progress.”
In addition to the headline fix to put all Microsoft Account and Entra ID token‑signing keys in hardware security modules or Azure confidential virtual machines, Bell said more than 90 percent of Microsoft’s internal productivity accounts have moved to phishing‑resistant multi factor authentication and that 90 percent of first‑party identity tokens are validated through a newly hardened software‑development kit.
Windows administrators from numerous organizations report widespread account lockouts triggered by false positives in the rollout of a new Microsoft Entra ID's
Since October 2024, Microsoft Defender Experts has observed and helped multiple customers address campaigns leveraging Node.js to deliver malware and other payloads that ultimately lead to information theft and data exfiltration.
In the past months Microsoft has seen multiple campaigns involving Node.js to deliver malware and other malicious payloads.
Microsoft on Tuesday issued a warning over the increasing use of Node.js for the delivery of malware and other malicious payloads.
The tech giant has been seeing such attacks aimed at its customers since October 2024 and some of the observed campaigns are still active in April 2025.
Microsoft Threat Intelligence Center (MSTIC) and Microsoft Security Response Center (MSRC) have discovered post-compromise exploitation of a zero-day elevation of privilege vulnerability in the Windows Common Log File System (CLFS) against a small number of targets. The targets include organizations in the information technology (IT) and real estate sectors of the United States, the financial sector in Venezuela, a Spanish software company, and the retail sector in Saudi Arabia. Microsoft released security updates to address the vulnerability, tracked as CVE-2025-29824, on April 8, 2025.
EncryptHub, a notorious threat actor linked to breaches at 618 organizations, is believed to have reported two Windows zero-day vulnerabilities to Microsoft, revealing a conflicted figure straddling the line between cybercrime and security research.
By leveraging Microsoft Security Copilot to expedite the vulnerability discovery process, Microsoft Threat Intelligence uncovered several vulnerabilities in multiple open-source bootloaders, impacting all operating systems relying on Unified Extensible Firmware Interface (UEFI) Secure Boot as well as IoT devices. The vulnerabilities found in the GRUB2 bootloader (commonly used as a Linux bootloader) and U-boot and Barebox bootloaders (commonly used for embedded systems), could allow threat actors to gain and execute arbitrary code.
Starting in December 2024, leading up to some of the busiest travel days, Microsoft Threat Intelligence identified a phishing campaign that impersonates online travel agency Booking.com and targets organizations in the hospitality industry. The campaign uses a social engineering technique called ClickFix to deliver multiple credential-stealing malware in order to conduct financial fraud and theft. […]
