I'm new here and I'm fairly new to crypto, however I found something odd and I'm not sure who to make aware of this so I'll just post it here.
Recently, my Poloniex account was compromised. It was likely as a result of a lapse in my judgement, but that isn't the issue. There were no withdrawals, just a series of trades buying really high and selling really low, as if someone was intentionally wasting my coins because they could not withdraw them. However, when looking further into the trades it was clear what was happening. A single party gained access to enough compromised accounts that they pooled their collective buying power together to manipulate the poloniex BTCD/XMR Market for the benefit of the hacker. Here are images of the unauthorized trades that occurred on my account and images of the market at that time.
https://i.imgur.com/Qu3KDGr.pnghttps://i.gyazo.com/abca78af587383ecd21ec76a62563d54.pngAs you can see, on the 18th of June (and possibly on the 17th) a market that normally sees small volumes and even smaller sudden price swings begins seeing a volume of over 200 BTCD flow through at the exact time my compromised account began making a series of trades selling low and buying high. From the image above you can see the trades my compromised account made did not come close to matching the amount that was suddenly pumped into and taken out of the market, it must have been a coordinated event. A large number of compromised accounts were exploited to sell their currency very low and buy currency very high so that the hacker could manipulate the market and funnel the assets from the compromised accounts which could not be withdrawn from without email verification to a different account.
I assume this is small in the grand scheme of things, however it really exposes a problem with Poloniex that needs to be addressed before it affects another, much larger market.
