pgp

# create a new key pair
gpg --full-generate-key

# get the fingerprints
gpg --list-public-keys

# get the base64 public key. --armor specifies the output to be ASCII
gpg --armor --export F73BA78DEDEDC2FBDF293EC92D5B77BC9E4457F3

# decrypt a message
gpg --decrypt temp.txt

Linux X-Paste

Script to paste into windows that don’t allow pasting. This is useful for VMs that dont have access to the clipboard.

#!/bin/bash


# set X display
export DISPLAY=":0"

sleep 0.5 # fat-finger protection

# get the clipboard content and send it as keypresses
xdotool type -- "$(xclip -o -selection clipboard)"

nginx

server {
        listen 80 default_server;
        listen [::]:80 default_server;

        #if ( $request_uri ~* "%0A|%0D" ) { return 403; }
        rewrite ^(.*)(\r|%0D)(.*)$ $1$3 permanent;
        rewrite ^(.*)(\s|%20)(.*)$ $1$3 permanent;


        root /var/www/html;

        # Add index.php to the list if you are using PHP
        index index.html index.htm index.nginx-debian.html;

        server_name _;

        location / {
                # First attempt to serve request as file, then
                # as directory, then fall back to displaying a 404.
                try_files $uri $uri/ =404;
                # proxy_pass http://localhost:8080;
                # proxy_http_version 1.1;
                # proxy_set_header Upgrade $http_upgrade;
                # proxy_set_header Connection 'upgrade';
                # proxy_set_header Host $host;
                # proxy_cache_bypass $http_upgrade;
        }

}

Explanation:

• ^ - Start of the string.
• (.*) - Captures any characters (the first part of the URI) and stores it in a capture group $1.
• (\r|%0D) - Looks for either a literal carriage return (\r) or its URL-encoded equivalent (%0D). This is the part we are trying to remove.
• (.*) - Captures the remaining part of the URI after the carriage return and stores it in capture group $3.
• $ - End of the string.
• $1$3 - This is the rewritten URL, which concatenates the first and third capture groups, effectively removing the carriage return (\r) or %0D.
• permanent - This specifies a permanent HTTP 301 redirect, which tells the browser that the redirect is permanent and the new URL should be used in future requests.

node.exe curl

node.exe can be used as an alternative to curl or Invoke-WebRequest

This can bypass restrictions like ThreatLocker, but should probably raise a flag in EDR tools. I havent seen anything yet.

#set URL
$url = "https://ipinfo.io/ip"

# Alternate curl/Invoke-WebRequest
& "C:\Program Files\Adobe\Adobe Creative Cloud Experience\libs\node.exe" -e "`$http=require('https');`$http.get('$url', `$res => `$res.pipe(process.stdout));"

places to look for node.exe:

• C:\Program Files\Common Files\Adobe\Creative Cloud Libraries\libs\node.exe
• C:\Program Files\Adobe\Adobe Creative Cloud Experience\libs\node.exe

SSH

Force close a ssh connection

Type: ~.

Sending an escape character ~ followed by a dot . will close the connection. The escape character only works at the beginning of a line, so you my need to press “Enter” first.

reverse tunnel

# ssh tunnel to make accessible from internet
ssh -N -f -R 0.0.0.0:55555:localhost:22 user@example.org
#            ^       ^internet port  ^local port
#            |
#            Specify wildcard. default is localhost*


# *you may need to edit /etc/ssh/sshd.config to set:
#  GatewayPorts=clientspecified

# upgraded to autossh to keep connection alive
autossh -N -f -R 127.0.0.2:55555:localhost:22 user@example.org
#                ^
#                |
#                Use different localhost addresses to organize multiple connections if youre using the same port

# look for connections
netstat  -nlp | grep 55555




# connecting to it

ssh -J user@example.org user@localhost -p 55555

Explanation

• -N - Do not execute a remote command.
• -f - Requests ssh to go to background just before command execution.
• -R - Specifies that connections to the given TCP port or Unix socket on the remote (server) host are to be forwarded to the local side.

socks proxy

ssh -N -D 8080 user@example.org

Proxmox

disable “No valid subscription” warning

Edit the Javascript file:

vim /usr/share/javascript/proxmox-widget-toolkit/proxmoxlib.js

Find the lines:

Ext.Msg.show({
  title: gettext('No valid subscription'),

Void the function:

void({ //Ext.Msg.show({
  title: gettext('No valid subscription'),

Restart the service:

systemctl restart pveproxy.service

openssl

# view cert
openssl s_ check cert dates

# view expiration cert dates
openssl s_client -connect example.org:443 | openssl x509 -noout -dates

OpenVPN

Making a OpenVPN entry point

enable ip forwarding

echo '1' >> /proc/sys/net/ipv4/ip_forward

# add iptables rules to route traffic from main interfaces to the vpn (i dont fully understand this)

iptables -t nat -A POSTROUTING -o tun+ -j MASQUERADE
iptables -A FORWARD -i ens+ -o tun+ -j ACCEPT
iptables -A FORWARD -o tun+ -j ACCEPT
iptables -A FORWARD -i tun+ -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT -i tun+ -j ACCEPT

preparing clients

clients dont need much. mainly, they just need a default route pointing to the entry server.

sudo ip route del default
sudo ip route add default via 10.0.0.173

you might be better off just using DHCP.

Firefox

about:config

browser.newtabpage.activity-stream.showSponsoredTopSites
    false

Simple File Uploads

#pip3 install uploadserver
#apt install qrencode
qrencode "http://$(hostname -I | tr -d ' '):8000/upload" -o - | feh - &
python3 -m uploadserver

Linux Mounting

# mount NFS share
sudo mount -t nfs <nfs_server:/path/to/share> /mnt

# mount windows partition that is hibernated
mount -t ntfs-3g -o remove_hiberfile /dev/<sdx0> /mnt

Vim Tricks

sudo trick

:w !sudo tee %

execute current line in bash

:.w !bash

Stupid Linux stuff

titty terminal

change tty[1-6] to titty[1-6]

sudo sed -r -i 's/(ti)?\\l/ti\\l/g' /etc/issue

mouse jiggler

# set X display
export DISPLAY=":0"

distance=10 # radius of the jiggle
delay=0.1   # time in seconds to wait between jiggles

while true
do
         randomAngle=$((1 + RANDOM % 360))
     inverseAngle=$(( ($randomAngle+180) % 360))

     # move random direction
         xdotool mousemove_relative --polar $randomAngle $distance
     sleep $delay   
     # return to initial position
         xdotool mousemove_relative --polar $inverseAngle $distance  
     sleep $delay
done

Pranks

tricks to run on peoples linux computers when they forget to lock them.

# increasingly slower bash startup
echo 'sleep 0.01' >> ~/.bashrc # or ~/.bash_profile