UPDATE: I got a response from LTC4YOU
"These are the e-mail addresses from the list, if you see yours in here, please change your passwords on every site/MPOS/etc that you might use. I do not know how old this particular dump is, I found it a few days ago and the site it was on has since removed it and updated their security.
I am posting this in hopes that anyone who has been recently hacked or who might be at risk of a hack is able to safeguard themselves.
Note that the passwords were PLAINTEXT, which means anyone could easily break into your email, the pool you mine, etc, if you reuse your passwords.
PLEASE REMEMBER TO USE GOOD PASSWORD SECURITY.
Edit: For now, I am declining to state where they come from, as the site has taken steps to increase their security and remove the ability to access their records. Shaming them does no good, and if they are equally careless in the future, I do not want to drive traffic to their site. I hope this is acceptable :)
Edit2: I will however say that this was not obtained from a mining site/MPOS site. Sorry, I had to go run some errands and stuff after I posted thisl [sic]"
It seems rather suspicious that Ryukaki won't disclose the site that experienced the breach, and many users are calling him out for this.
"Your edit is complete bullshit. Sites need to be open an honest about this kind of thing. Hiding a leak like this only means that I trust them even less for the "fix" they made."
However, many have reported that the leaked email addresses are from ltc4you.com. Several leaked email addresses contain terms such as "ltc" and "faucet", and some users who registered on that site used unique email addresses, which were found on the list.
"It's from website LTC4You.com because i registered to this website only with one mail and it's in the list."
While the Paste does not contain any passwords, it's safe to assume that passwords may have also been compromised. As such, if you use the same password everywhere, change it ASAP. It's always a good idea to use a different password on every website. Programs such as LastPass and 1Password make this very easy.
As you would expect from a massive email address leak, those who were affected have seen a sudden increase in spam,
This is frustrating news for anyone affected.
I contacted ltc4you.com about this, but have received no response yet. I'll post an update when/if they respond. I received a response from LTC4YOU. See the top of this post.