An unidentified hacker hijacked a coinHives DNS server this afternoon. He or she replaced the javaScript bowser miner with a malicious version. They were out for miner's Monero hot vWallets. This happened on Wednesday night. The compromise was discovered the next day and fixed right away. The hacker got into their cloudflare and replaced the DNS documents and redirected to a new IP. The new server did the push to that contained the hardcoded key.
Thousands of computers from around the world were redirected to the compromised site. The event took a course of about 6 hours till it was noticed of the redirect.
The blame for the accident was the re-use of an old password. I recommend you use add blockers to try to filter these out as these new javaScript codes are increasingly growing in popularity among the hacking community.