Thank you for getting in touch and please accept my apologies for the delay with this update.

I am very sorry but your account was compromised through your login credentials and the attacker traded on other markets with your funds. Unfortunately as you did not have 2FA enabled, these credentials were all the attacker required to be able to access your account.

We would like you to know that we are still investigating this very complex issue and there is a remote possibility that some of the stolen funds can be recovered.
 
We will do our best however there is no guarantee that this will be successful.
 
I am sorry again to hear that this unfortunate situation has occurred, however we would also like to advise you to please be very careful in the future with your operational security. Never use the same password on different sites, keep your email account and Poloniex account secured with 2FA and do not download any software to the computer you are handling your trading accounts with unless you are ABSOLUTELY sure it is safe.


Sincerely,
Poloniex Support Team

Ticket: https://poloniex.freshdesk.com/helpdesk/tickets/298363

this is what i got in reply from poloniex after 40 days.   My account is hacked almost in similar way,others have mentioned. going through the google searches , i found that these kind of "hack & unauthorized trades"
 happened in almost all of the cases between may to july end. now there is no reporting of cases like this . neither there was any before may. i seriously doubt it's an organized hack with the involvement of some insider