Well, guess what happened to me today after 12 years in SL without any issue? My account has been hacked (yes hacked as in they found my logins infos to log my avatar, teleported to some escort place and emptied my account there (silly way to empty an account if you ask me but whatever).
Now I wait for Linden Lab to wake up and solve my issue, and make SL more secure but maybe I'm dreaming too much that they will ever wake up.
PS: no my password wasn't easy to guess, no I didn't use some obscure 3rd party app, yes I changed my password through the years, and no I don't spend my SL money on SL escorts