Is there risk to holding USDT?

Good afternoon, I am relatively new to the world of cryptocurrencies and am currently considering adding USDT to my portfolio. However, I have heard conflicting opinions about the stability and safety of USDT. Could you please provide some insight into the potential risks associated with holding USDT? I am particularly concerned about its peg to the US dollar and whether it could potentially decouple in times of market volatility. Additionally, are there any known security vulnerabilities or hacking risks associated with USDT that I should be aware of? Thank you for your time and expertise.