Google Gemini Hit by Unfixed ASCII Smuggling AI Attack in 2025
In October 2025, a newly disclosed ASCII smuggling attack targeting Google’s Gemini AI assistant exposed a significant security vulnerability stemming from the model's processing of hidden Unicode payloads. Security researcher Viktor Markopoulos demonstrated that attackers could leverage invisible Unicode characters in Calendar invites or emails, prompting Gemini to execute unseen instructions and alter its behavior without user awareness. Notably, the exploit could automate data extraction or spoof identities within Google Workspace integrations, increasing risk for both users and enterprises. Despite the demonstrated risks, Google chose not to address the vulnerability, citing its overlap with social engineering tactics. This incident underscores the heightened threat posed by AI/ML attacks against widely integrated platforms. As LLMs increasingly automate workflows and access sensitive data, adversarial prompt manipulation and Unicode character abuse are becoming urgent areas for organizational security reviews and regulatory scrutiny.
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