Quote from: tobeaj2mer01 on July 25, 2014, 08:52:25 AM

@DEV, a guy named porqupine found a vulnerability, it can be used to attack XCP and cause our money lost, could you fix this issue

https://bitcointalk.org/index.php?topic=708879.0

His post in reddit:
Please don't feed the troll:
Please respond to the fact that I'm well known in this community, that there is working source code, and you've both refused my offer to make a CFD so I could demonstrate the vulnerability, and blocked all my posts from the bitcointalk thread.
Why would I spend months designing a website for CFD's and than try to discredit them? And further if there is no exploit, why wouldn't you make a CFD and prove me wrong, rather than trying to censor me?

http://www.reddit.com/r/counterparty/comments/2bmlg6/ann_counterparty_exploit_public_disclosure/

Please see PhantomPhreak's post directly above yours. The feature is being disabled in order to deal with the bug.

EDIT: to be perfectly clear, the bug is such that by making small CFDs against a large one, you can effectively increase the latter's exposure. This is an implementation issue, and is being fixed.