Memcached is a popular open-source distributed caching system that allows objects to be stored in memory. It’s widely used by thousands of websites, including Facebook, Flickr, Twitter, Reddit, YouTube, and Github. Cybercriminals have figured out a way to abuse widely-used servers to launch over 51,000 times powerful DDoS attacks than their original strength. The attack is the most prominent amplification method ever used in the wild so far, according to researchers at Cloudflare and Qihoo 360.
Source: https://thehackernews.com/2018/02/memcached-amplification-ddos.html