
ChatGPT Prompt Injection Flaw Exposed Gmail Data Through Hidden Cross-Account Channels
In September 2026, Check Point Research disclosed a critical vulnerability in OpenAI's ChatGPT that allowed attackers to inject malicious prompts that could silently exfiltrate user data from connected applications like Gmail. The attack exploited a shared internal JFrog Artifactory service used by ChatGPT's isolated containers, creating an unauthorized communication channel between different user accounts. Attackers could plant instructions through shared conversations, custom GPTs, or user-pasted prompts that would execute hidden data theft operations while displaying normal responses to victims. OpenAI confirmed the vulnerability and took the internal service offline after disclosure. This incident highlights the emerging risks of AI systems as attack vectors, particularly as organizations increasingly integrate AI tools with sensitive business applications and data sources, making prompt injection attacks a critical new threat category requiring immediate security attention.
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