https://github.com/MatheuZSecurity/D3m0n1z3dShell

• Auto Generate SSH keypair for all users
• APT Persistence
• Crontab Persistence
• Systemd User level
• Systemd Root Level
• Bashrc Persistence
• Privileged user & SUID bash
• LKM Rootkit Modified, Bypassing rkhunter & chkrootkit
• LKM Rootkit With file encoder. persistent icmp backdoor and others features.
• ICMP Backdoor
• LD_PRELOAD Setup PrivEsc
• Static Binaries For Process Monitoring, Dump credentials, Enumeration, Trolling and Others Binaries.

https://gist.github.com/grahamhelton/b78f9238544e63c0046b4a20e3aed188

Cron job to put your SSH key in authorized keys