TikTok app on iPhone has been copying the contents of the “clipboard”. Now that your clipboard is shared across devices, stuff you copied to the clipboard on a Mac can end up on an iPhone and then intercepted by TikTok. TikTok will have to change the feature, moving forward. Whether something similar is done on Android is not known.
Ever copy a password to your clipboard? Well, duh, we all have!
Source: Warning—Apple Suddenly Catches TikTok Secretly Spying On Millions Of iPhone Users