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• AI brands as bait: How threat actors are using the AI hype in social engineering

As threat actors operationalize AI to accelerate attacks, they are also leveraging the wider global interest around AI itself as a social engineering lure.

• The Gentlemen ransomware: Dissecting a self-propagating Go encryptor

Microsoft Threat Intelligence presents a comprehensive analysis of The Gentlemen, a Go-based ransomware deployed by affiliates of Storm-2697 that combines per-file ephemeral key encryption with an aggressive self-propagation module to deploy itself across an entire network using series of simultaneous lateral movement techniques per target.

• Exposing Fox Tempest: A malware-signing service operation

Fox Tempest is a financially motivated threat actor operating a malware‑signing‑as‑a‑service (MSaaS) used by other cybercriminals, including Vanilla Tempest and Storm groups, to more effectively distribute malicious code, including ransomware.

• Kazuar: Anatomy of a nation-state botnet

Kazuar, a sophisticated malware family attributed to the Russian state actor Secret Blizzard, has been under constant development for years and continues to evolve in support of espionage-focused operations.

• Undermining the trust boundary: Investigating a stealthy intrusion through third-party compromise

Microsoft Incident Response investigated an attack operated through legitimate and trusted administrative mechanisms to blend seamlessly into routine operations and remain undetected demonstrating that intrusions have increasingly avoided using noisy exploits, obvious malware, or custom tooling, instead leveraging systems that organizations already trust within their environments.

• Breaking the code: Multi-stage ‘code of conduct’ phishing campaign leads to AiTM token compromise

Microsoft Defender Research observed a large-scale credential theft campaign that exemplifies this trend, using code of conduct-themed lures, a multi-step attack chain, and legitimate email services to distribute fully authenticated messages from attacker-controlled domains.

• Email threat landscape: Q1 2026 trends and insights

In early 2026, email threats increased with a rise in credential phishing, QR code phishing, and CAPTCHA-gated campaigns, highlighted by Microsoft’s disruption of the Tycoon2FA phishing platform which led to a 15% volume decrease and shifts in threat actor tactics.

• Dissecting Sapphire Sleet’s macOS intrusion from lure to compromise

The Microsoft Defender Security Research Team uncovered a sophisticated macOS intrusion campaign attributed to the North Korean threat actor Sapphire Sleet that abuses user driven execution and social engineering to bypass macOS security protections and steal credentials, cryptocurrency assets, and sensitive data.

• Investigating Storm-2755: “Payroll pirate” attacks targeting Canadian employees

Microsoft Incident Response – Detection and Response Team (DART) researchers observed an emerging, financially motivated threat actor, tracked as Storm-2755, compromising Canadian employee accounts to gain unauthorized access to employee profiles and divert salary payments to attacker-controlled accounts.

• 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.

• 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.

• 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.