MailEnable SMTP Connector Service SPF Record Crafted Lookup DoS

#
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(22411);
  script_version("1.22");
  script_cvs_date("Date: 2018/07/14  1:59:37");

  script_cve_id("CVE-2006-4616");
  script_bugtraq_id(20091);

  script_name(english:"MailEnable SMTP Connector Service SPF Record Crafted Lookup DoS");
  script_summary(english:"Checks version of MailEnable's MESMTPC.exe.");

  script_set_attribute(attribute:"synopsis", value:
"The remote SMTP server is affected by a denial of service
vulnerability.");
  script_set_attribute(attribute:"description", value:
"The remote host is running MailEnable, a commercial mail server for
Windows.

The SMTP server bundled with the version of MailEnable installed on
the remote host is affected by a flaw in which SPF lookups for domains
with large records may result in a NULL pointer exception in the SMTP
service. An unauthenticated, remote attacker can exploit this issue to
crash the affected service.");
  script_set_attribute(attribute:"see_also", value:"http://www.mailenable.com/hotfix/");
  script_set_attribute(attribute:"solution", value:
"Apply Hotfix ME-10014.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2006/09/05");
  script_set_attribute(attribute:"plugin_publication_date", value:"2006/09/19");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:mailenable:mailenable");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"SMTP problems");

  script_copyright(english:"This script is Copyright (C) 2006-2018 Tenable Network Security, Inc.");

  script_dependencies("smtpserver_detect.nasl", "smb_hotfixes.nasl");
  script_require_keys("SMB/Registry/Enumerated");
  script_require_ports("Services/smtp", 25, 139, 445);

  exit(0);
}

include("audit.inc");
include("smb_func.inc");
include("smb_hotfixes.inc");
include("smb_hotfixes_fcheck.inc");
#include("smtp_func.inc");
include("misc_func.inc");
# comment out: remote check would fail in agent/NSX mode

#smtp_port = get_kb_item("Services/smtp");
#if (!smtp_port) port = 25;
#if (!get_port_state(smtp_port)) exit(0);
#if (get_kb_item('SMTP/'+smtp_port+'/broken')) exit(0);


# Make sure the banner corresponds to MailEnable.
#banner = get_smtp_banner(port:smtp_port);
#if (
#  !banner ||
#  !egrep(pattern:"Mail(Enable| Enable SMTP) Service", string:banner)
#) exit(0);


# Connect to the appropriate share.
get_kb_item_or_exit("SMB/Registry/Enumerated");
port    =  kb_smb_transport();
login   =  kb_smb_login();
pass    =  kb_smb_password();
domain  =  kb_smb_domain();

if(! smb_session_init()) audit(AUDIT_FN_FAIL, 'smb_session_init');

rc = NetUseAdd(login:login, password:pass, domain:domain, share:"IPC$");
if (rc != 1)
{
  NetUseDel();
  audit(AUDIT_SHARE_FAIL,"IPC$");
}


# Connect to remote registry.
hklm = RegConnectRegistry(hkey:HKEY_LOCAL_MACHINE);
if (isnull(hklm))
{
  NetUseDel();
  audit(AUDIT_REG_FAIL);
}


# Determine location of MailEnable's application directory.
path = NULL;
key = "SOFTWARE\Mail Enable\Mail Enable";
key_h = RegOpenKey(handle:hklm, key:key, mode:MAXIMUM_ALLOWED);
if (!isnull(key_h)) {
  item = RegQueryValue(handle:key_h, item:"Application Directory");
  if (!isnull(item)) path = item[1];
  RegCloseKey(handle:key_h);
}
RegCloseKey(handle:hklm);
if (isnull(path))
{
  NetUseDel();
  exit(0);
}
NetUseDel(close:FALSE);


# Check version of MESMTPC.exe
share = ereg_replace(pattern:"^([A-Za-z]):.*", replace:"\1$", string:path);
exe = ereg_replace(pattern:"^[A-Za-z]:(.*)", replace:"\1\MESMTPC.exe", string:path);

if (
  is_accessible_share(share:share) &&
  hotfix_check_fversion(file:"MESMTPC.exe",  path:path, version:"1.0.0.20") == HCF_OLDER
)
{
  security_warning(port);
  hotfix_check_fversion_end();
  exit(0);
}
else
{
  hotfix_check_fversion_end();
  audit(AUDIT_HOST_NOT, 'affected');
}