There is no official word yet other than their Twitter stating security issues. I can confirm via at least 4 separate people that their BTC have been split and sent to different wallets tracking it through the blockchain. This is their vague Tweet: https://twitter.com/CoinexPW/status/445302786927104000
Whether or not the supposed attack is limited to just Bitcoin remains to be seen. I am trying to get more information.
Erundook has deleted his Github account: https://github.com/erundook and also deleted his Twitter account: https://twitter.com/erundook
His NPM profile is still up however with his full name, email address, etc: https://www.npmjs.org/~erundook
I am no private investigator or law enforcement officer, but it is looking like Erundook or should I say Vitaly A. Sorokin is trying to erase himself from the Internet here...