Varonis found a “Reprompt” attack that let a single link hijack Microsoft Copilot Personal sessions and exfiltrate data; Microsoft patched it in January 2026.

Microsoft has pushed back against claims that multiple prompt injection and sandbox-related issues raised by a security ...

"Now that the code is open source, what does it mean for you? Explore the codebase and learn how agent mode is implemented, what context is sent to LLMs, and how we engineer our prompts. Everything, ...

Copilot is quickly becoming the quiet organizer behind many people’s workdays, turning scattered files, emails, and chats ...