Google Gemini Prompt Injection Flaw Exposed Private Calendar Data via Malicious Invites
Jan 19, 2026
Artificial Intelligence / Vulnerability
Cybersecurity researchers have disclosed details of a security flaw that leverages indirect prompt injection targeting Google Gemini as a way to bypass authorization guardrails and use Google Calendar as a data extraction mechanism. The vulnerability, Miggo Security's Head of Research, Liad Eliyahu, said, made it possible to circumvent Google Calendar's privacy controls by hiding a dormant malicious payload within a standard calendar invite. "This bypass enabled unauthorized access to private meeting data and the creation of deceptive calendar events without any direct user interaction," Eliyahu said in a report shared with The Hacker News. The starting point of the attack chain is a new calendar event that's crafted by the threat actor and sent to a target. The invite's description embeds a natural language prompt that's designed to do their bidding, resulting in a prompt injection. The attack gets activated when a user asks Gemini a completely inno...
