Apple users reported being logged out of their iCloud/Apple ID accounts over the last couple of days, requiring them to create a new password.
The issue appeared to begin late Friday evening or early Saturday morning. Users reported being logged out of their iCloud/Apple accounts, including any devices that were checking iCloud email with app-specific passwords.
In the case, I can attest to the widespread nature of the issue. Although I don’t use Apple devices, I do have an old iCloud account that I still use for email. Both of my personal computers, and my phone, started throwing authentication errors early Saturday morning.
A trip to https://appleid.apple.com/ revealed that my account was locked, requiring me to go through the steps to unlock it, choose an entirely new password, and set up app-specific passwords so the email clients on my devices could once again access my email account.
There has been no word from Apple regarding what happened, why the reset was forced on so many users, or if this is going to be a common occurrence.