Writing in the company bog, Wiz said that scans of DeepSeek's infrastructure showed that the company had accidentally left more than a million lines of data available unsecured. Those included digital software keys and chat logs that appeared to capture user prompts sent to the company's free AI assistant.

Wiz's chief technology officer Ami Luttwak said DeepSeek quickly secured the data after his firm alerted them.

"They took it down in less than an hour. But this was so simple to find we believe we're not the only ones who found it."

DeepSeek's practically overnight success following the launch of its AI assistant has thrilled China and sparked anxiety in America. The Chinese company's apparent ability to match OpenAI's capabilities at a much lower cost has posed questions over the sustainability of the business models and profit margins of US AI giants such as Nvidia and Microsoft.

By Monday, it had overtaken US rival ChatGPT in downloads from Apple's App Store, triggering a global selloff in tech shares.

How long that will that last as the AI, which stores personal data in Chinese servers, might break EU GDPR (and has already been banned in Italy) is anyone’s guess. The US will likely come down hard on it as part of its Chinese trade war.