Microsoft has introduced a new capability in Defender for Office 365 to protect against prompt injection attacks, which target AI-powered email workflows, such as Microsoft 365 Copilot.
This update reflects the evolving threat landscape, where attackers increasingly attempt to manipulate AI systems instead of directly deceiving human users.
Prompt injection attacks involve embedding malicious instructions within email content that an AI assistant processes. Rather than using traditional phishing tactics like fake links or urgent messages, attackers craft text designed to influence how an AI model interprets and responds to a communication.
These malicious instructions can be found in the email body, subject line, attachments, or even hidden elements like invisible text or encoded content.
