Security researchers sometimes find artifacts like:
wget https://signin.samsung.com/backup/old.key and then demonstrate the impact of key compromise. singin.samsung.com.key is not a real, active vulnerability on Samsung’s infrastructure. It is most likely a typographical mutation of signin.samsung.com combined with a sensitive file extension – useful only as a hypothetical case study in web application security. singin.samsung.com.key
Always validate domain names, never serve private keys over HTTP, and assume that attackers are looking for exactly these kinds of mistakes – even those hidden behind a simple typo. never serve private keys over HTTP