malicious hackers have previously embedded monero mining code into websites and apps seeking profit for themselves. in late 2017 malware and antivirus service providers blocked a javascript implementation of monero miner coinhive that was embedded in websites and apps, in some cases by hackers. coinhive generated the script as an alternative to advertisements; a website or app could embed it, and use website visitor's cpu to mine the cryptocurrency while the visitor is consuming the content of the webpage, with the site or app owner getting a percentage of the mined coins. some websites and apps did this without informing visitors, and some hackers implemented it in way that drained visitors' cpus. as a result the script was blocked by companies offering ad blocking subscription lists, antivirus services, and antimalware services.