Prompt Injection in AI Agents: How Emails and Documents Hijack Business Workflows and How to Prevent It

1Key Takeaways

• The most dangerous instruction your AI agent receives may not come from an employee.
• It may arrive inside a customer email, résumé, invoice, support ticket, or shared document.
• In July 2026, researchers disclosed AgentForger, a flaw that let phishing links preconfigure malicious workplace agents before users deployed them.
• The controversy is bigger than one patched product: enterprises keep giving AI agents access to inboxes, files, CRMs, and payment systems while treating every document as….