Earlier this week T-Mobile acknowledged that hackers had breached its security and stolen data on 40 million of its customers. The hackers claim they actually stole data on 100 million people, and were found selling the information on a forum for 6 bitcoin, or about $280,000 at the time of the listing.
Once a consumer's information has been compromised there is not way to undo that action, but there are ways that people can mitigate the potential risks tied to having their data leaked.
While "assume the worst" is advice unlikely to appear in any self-help books, it is actually a good policy for protecting yourself online. If you act as though your information has already been compromised and take appropriate security steps, then you will be protected when - or if - your data actually is stolen. Those steps include changing your passwords, setting up two-factor authentication on appropriate accounts, keeping a vigilant watch on your bank account and ordering credit reports to ensure no one is using your identity to purchase items.