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Windows
Microsoft’s new cloud PCs place AI agents under enterprise controls

Microsoft’s Windows 365 for Agents, a cloud PC platform for agentic workloads, runs AI agents in secure environments. Organizations can direct agents with natural language to …

hand
AI chatbot recommendations lure users to cryptojacking malware sites

Cybercriminals are using AI chatbot interactions alongside poisoned search results to direct users to malicious download sites in an active cryptojacking campaign, Microsoft …

Microsoft SharePoint
High-severity SharePoint RCE bug patched by Microsoft (CVE-2026-45659)

Microsoft has released patches for a high-severity remote code execution vulnerability (CVE-2026-45659) in SharePoint that may be exploited in low-complexity attacks. It …

Microsoft 365 phishing
Microsoft 365 users targeted by new phishing threat that bypasses MFA

Microsoft 365 access tokens are being targeted by an emerging Phishing-as-a-Service (PhaaS) platform called Kali365, the FBI is warning. First observed in April 2026, Kali365 …

AI agents
Microsoft open-sources tools for designing and testing AI agents

Microsoft has open-sourced two tools aimed at bringing security discipline to AI agent development: Clarity, a structured design review tool, and RAMPART, a continuous testing …

Microsoft
Microsoft Defender vulnerabilities exploited in the wild (CVE-2026-41091, CVE-2026-45498)

Attackers are exploiting two Microsoft Defender vulnerabilities (CVE-2026-41091 and CVE-2026-45498), Microsoft acknowledged and CISA confirmed by adding them to its Known …

access
Microsoft provides mitigation for “YellowKey” BitLocker bypass flaw (CVE-2026-45585)

Microsoft is working on a fix for CVE-2026-45585 (aka “Yellowkey”), a vulnerability that can be used by attackers to bypass protections offered by BitLocker, the …

infostealers
New macOS infostealer impersonates Apple, Microsoft, and Google in a single attack chain

A SHub macOS infostealer variant called Reaper impersonates Apple, Microsoft, and Google to trick users into executing malicious code, then targets browser data, password …

door
The AI backdoor your security stack is not built to see

Enterprises deploying LLMs have spent the past two years building defenses around a reasonable assumption: malicious behavior leaves a trace in the input. Scan for suspicious …

Microsoft Exchange
Unpatched Microsoft Exchange Server vulnerability exploited (CVE-2026-42897)

A critical cross-site scripting (XSS) vulnerability (CVE-2026-42897) in Microsoft Exchange Server is being exploited by attackers, Microsoft warned on Thursday. A permanent …

WinUI agent plugin
Microsoft’s WinUI agent plugin trims token use by over 70% during development

Microsoft published a plugin on May 13 that lets GitHub Copilot CLI and Claude Code drive the full WinUI 3 development cycle, from project scaffolding through signed MSIX …

Microsoft Copilot Studio
Microsoft turns Copilot Studio into an AI agent control center

The Microsoft Copilot Studio April 2026 updates improve visibility and governance for admins and expand workflow capabilities for managing agents. Copilot surfaces agent …

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