News of a vulnerability found in Samsung's Account feature broke cover two days back, a vulnerability that Samsung has already fixed via an update. Basically, data such as login information was being transferred to Samsung's servers in plain text, making it possible for hackers to intercept the data – however, the company has made a statement that no data was stolen or spied upon, and that it was only possible to exploit the vulnerability when a new Samsung account was created.
That's good to hear, but as always, it would be best to change your Samsung Account password as soon as possible, just in case. Hopefully, such vulnerabilities won't arise in the future, and if they do, Samsung will be quick to fix them up.