There's been quite a few reports of people who use TeamViewer having their computers hijacked and even their PayPal accounts being raided:
https://www.reddit.c...ease_post_your/
https://www.reddit.c...ey_are_denying/
http://www.theregist..._breach_report/
It's been denied by TeamViewer in official statements (1, 2) but if you use TeamViewer it might be a good idea to keep a close eye on it and maybe keep it completely closed when you're not using it.
