Git/ssh-audit
1
0
Fork 0
mirror of https://github.com/jtesta/ssh-audit.git synced 2026-01-12 00:12:06 +01:00
Code Issues Packages Projects Releases Wiki Activity
Page: Redhat & Fedora
Pages
Arch ArubaOS Switch (AOS S) 16.11 Dropbear 2022.83 Extreme Networks (Fabric Engine and Switch Engine) Fedora CoreOS Flatcar Linux Fortinet FortiOS FreeBSD Home Mikrotik RouterOS OPNsense 20.7 and newer Proxmox VE 7.3 6 Redhat & Fedora SSH Hardening Guides Index Synology DSM Ubuntu 22.04 LTS Client Linux Mint 21 Client Void Linux Windows 11 macOS 13 (Ventura) & 14 (Sonoma)
Clone
4
Redhat & Fedora
joe81tx edited this page 2025-12-29 09:54:14 -06:00
Table of Contents

Tested against:

  • Red Hat Enterprise Linux (RHEL) 10.1
  • Fedora 43

Server

printf "KexAlgorithms mlkem768x25519-sha256,sntrup761x25519-sha512,sntrup761x25519-sha512@openssh.com,curve25519-sha256,curve25519-sha256@libssh.org\nCiphers aes256-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-gcm@openssh.com,aes128-ctr\nMACs hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,umac-128-etm@openssh.com\nHostKeyAlgorithms sk-ssh-ed25519-cert-v01@openssh.com,ssh-ed25519-cert-v01@openssh.com,rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-256-cert-v01@openssh.com,sk-ssh-ed25519@openssh.com,ssh-ed25519,rsa-sha2-512,rsa-sha2-256\nCASignatureAlgorithms sk-ssh-ed25519@openssh.com,ssh-ed25519,rsa-sha2-512,rsa-sha2-256\nHostbasedAcceptedAlgorithms sk-ssh-ed25519-cert-v01@openssh.com,ssh-ed25519-cert-v01@openssh.com,rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-256-cert-v01@openssh.com,sk-ssh-ed25519@openssh.com,ssh-ed25519,rsa-sha2-512,rsa-sha2-256\nPubkeyAcceptedAlgorithms sk-ssh-ed25519-cert-v01@openssh.com,ssh-ed25519-cert-v01@openssh.com,rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-256-cert-v01@openssh.com,sk-ssh-ed25519@openssh.com,ssh-ed25519,rsa-sha2-512,rsa-sha2-256\n" | sudo tee /etc/ssh/sshd_config.d/01-hardened-ssh.conf

sudo rm -f /etc/ssh/ssh_host_*
sudo ssh-keygen -t rsa -b 4096 -f /etc/ssh/ssh_host_rsa_key -N ""
sudo ssh-keygen -t ed25519 -f /etc/ssh/ssh_host_ed25519_key -N ""
sudo systemctl restart sshd

Client

mkdir -p -m 0700 ~/.ssh; printf "\nHost *\n  Ciphers aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr\n\n  KexAlgorithms mlkem768x25519-sha256,sntrup761x25519-sha512,sntrup761x25519-sha512@openssh.com,curve25519-sha256,curve25519-sha256@libssh.org,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group-exchange-sha256\n\n  MACs hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,umac-128-etm@openssh.com\n\n  HostKeyAlgorithms sk-ssh-ed25519-cert-v01@openssh.com,ssh-ed25519-cert-v01@openssh.com,rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-256-cert-v01@openssh.com,sk-ssh-ed25519@openssh.com,ssh-ed25519,rsa-sha2-512,rsa-sha2-256\n\n  CASignatureAlgorithms sk-ssh-ed25519@openssh.com,ssh-ed25519,rsa-sha2-512,rsa-sha2-256\n\n  HostbasedAcceptedAlgorithms sk-ssh-ed25519-cert-v01@openssh.com,ssh-ed25519-cert-v01@openssh.com,sk-ssh-ed25519@openssh.com,ssh-ed25519,rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-512,rsa-sha2-256-cert-v01@openssh.com,rsa-sha2-256\n\n  PubkeyAcceptedAlgorithms sk-ssh-ed25519-cert-v01@openssh.com,ssh-ed25519-cert-v01@openssh.com,sk-ssh-ed25519@openssh.com,ssh-ed25519,rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-512,rsa-sha2-256-cert-v01@openssh.com,rsa-sha2-256\n" >> ~/.ssh/config