Athlete surveillance warnings cloud China's Winter Olympics

Researchers said a virus-monitoring app all attendees must use was found to have a "simple but devastating" encryption flaw

A growing number of Western nations and cybersecurity groups have issued digital surveillance warnings for next month's Winter Olympics in Beijing, with some advising foreign athletes to leave personal phones and laptops at home.

National Olympic associations in the United States, Canada, the United Kingdom and Australia have advised athletes to leave their personal devices at home and use temporary burner phones if possible while in China for the Games.