Editer le fichier /etc/sysctl.conf

fs.protected_hardlinks = 1
fs.protected_symlinks = 1
fs.suid_dumpable = 0
kernel.kptr_restrict = 2
kernel.panic = 60
kernel.panic_on_oops = 60
kernel.randomize_va_space = 2
kernel.sysrq = 0
kernel.yama.ptrace_scope = 1
vm.swappiness = 10
net.ipv4.conf.all.accept_redirects = 0
net.ipv4.conf.all.log_martians = 1
net.ipv4.conf.all.secure_redirects = 0
net.ipv4.conf.all.send_redirects = 0
net.ipv4.conf.default.accept_redirects = 0
net.ipv4.conf.default.accept_source_route = 0
net.ipv4.conf.default.log_martians = 1
net.ipv4.conf.default.send_redirects = 0
net.ipv6.conf.default.accept_ra = 0
net.ipv6.conf.default.accept_ra_defrtr = 0
net.ipv6.conf.default.accept_ra_pinfo = 0
net.ipv6.conf.default.accept_redirects = 0
net.ipv6.conf.default.autoconf = 0
net.ipv6.conf.default.dad_transmits = 0
net.ipv6.conf.default.max_addresses = 1
net.ipv6.conf.default.router_solicitations = 0
net.ipv6.conf.eth0.accept_ra_rtr_pref = 0