I just pwned user & root flag of Cypher from Hack The Box! I will be publishing a full walkthrough once the machine is retired (in accordance with Hack The Box Terms of Service). The machine was relatively easy compared to other medium machines. A critical analysis of what this machine teaches us to defend on our systems will also be made available once the machine retires.
You can find Hack The Box Terms of Service here: https://www.hackthebox.com/tos
You can find Hack The Box guidelines for publishing walkthroughs here: https://help.hackthebox.com/en/articles/5188925-streaming-writeups-walkthrough-guidelines