Threat intelligence

The Microsoft Threat Intelligence community is made up of world-class experts, security researchers, analysts, and threat hunters who analyze 100 trillion signals daily to discover threats and deliver timely and timely, relevant insight to protect customers. See our latest findings, insights, and guidance.

Refine Results

Filtered by

Clear All

Threat intelligence
Newest to Oldest

Refine results

Sort By

Content Type

Topic

Products and services

Publish date

Start Date

End Date

April 7

9 min read

SOHO router compromise leads to DNS hijacking and adversary-in-the-middle attacks

Executive summary Forest Blizzard, a threat actor linked to the Russian military, has been compromising insecure home and small-office internet equipment like routers, then modifying their settings in ways that turn them into part of the actor’s malicious infrastructure.
April 6

12 min read

Storm-1175 focuses gaze on vulnerable web-facing assets in high-tempo Medusa ransomware operations

The financially motivated cybercriminal threat actor Storm-1175 operates high-velocity ransomware campaigns that weaponize recently disclosed vulnerabilities to obtain initial access, exfiltrate data, and deploy Medusa ransomware.
April 1

16 min read

Mitigating the Axios npm supply chain compromise

On March 31, 2026, the popular HTTP client Axios experienced a supply chain attack, causing two newly published npm packages for version updates to download from command and control (C2) that Microsoft Threat Intelligence has attributed to the North Korean state actor Sapphire Sleet.
March 19

14 min read

When tax season becomes cyberattack season: Phishing and malware campaigns using tax-related lures

During tax season, threat actors reliably take advantage of the urgency and familiarity of time-sensitive emails, including refund notices, payroll forms, filing reminders, and requests from tax professionals, to push malicious attachments, links, or QR codes.
Retain Microsoft Security Experts

Microsoft Security Experts are now available to strengthen your team with managed security services. Learn how to defend against threats with security experts.

Get started
March 12

9 min read

Storm-2561 uses SEO poisoning to distribute fake VPN clients for credential theft

Storm-2561 uses SEO poisoning to push fake VPN downloads that install signed trojans and steal VPN credentials.
March 6

21 min read

AI as tradecraft: How threat actors operationalize AI

Threat actors are operationalizing AI to scale and sustain malicious activity, accelerating tradecraft and increasing risk for defenders, as illustrated by recent activity from North Korean groups such as Jasper Sleet and Coral Sleet (formerly Storm-1877).
March 4

15 min read

Inside Tycoon2FA: How a leading AiTM phishing kit operated at scale

Tycoon2FA has become a leading phishing-as-a-service (PhaaS) platforms, enabling campaigns that reach over 500,000 organizations monthly, prompting Microsoft’s Digital Crimes Unit (DCU) to work with Europol and industry partners to facilitate a disruption of Tycoon2FA’s infrastructure and operations.
January 14

16 min read

Inside RedVDS: How a single virtual desktop provider fueled worldwide cybercriminal operations

Microsoft’s investigation into RedVDS services and infrastructure uncovered a global network of disparate cybercriminals purchasing and using to target multiple sectors.
Modernize your Security Operations Center with Microsoft Sentinel

Microsoft Sentinel is a cloud-native SIEM solution powered by AI and automation that delivers intelligent security analytics across your entire enterprise.

Learn more
January 6

16 min read

Phishing actors exploit complex routing and misconfigurations to spoof domains

Threat actors are exploiting complex routing scenarios and misconfigured spoof protections to send spoofed phishing emails, crafted to appear as internally sent messages.
December 15, 2025

16 min read

Defending against the CVE-2025-55182 (React2Shell) vulnerability in React Server Components

CVE-2025-55182 (also referred to as React2Shell and includes CVE-2025-66478, which was merged into it) is a critical pre-authentication remote code execution (RCE) vulnerability affecting React Server Components and related frameworks.
December 9, 2025

10 min read

Shai-Hulud 2.0: Guidance for detecting, investigating, and defending against the supply chain attack

The Shai‑Hulud 2.0 supply chain attack represents one of the most significant cloud-native ecosystem compromises observed recently.
November 3, 2025

10 min read

SesameOp: Novel backdoor uses OpenAI Assistants API for command and control

Microsoft Incident Response – Detection and Response Team (DART) researchers uncovered a new backdoor that is notable for its novel use of the OpenAI Assistants Application Programming Interface (API) as a mechanism for command-and-control (C2) communications.

Threat intelligence

Filtered by

Refine results

Retain Microsoft Security Experts

Modernize your Security Operations Center with Microsoft Sentinel

Get started with Microsoft Security