Microsoft Windows: Enable insecure guest logons

##############################################################################
# OpenVAS Vulnerability Test
# $Id: win_insecure_guest_logons.nasl 11337 2018-09-11 14:23:53Z emoss $
#
# Check value for Enable insecure guest logons
#
# Authors:
# Emanuel Moss <[email protected]>
#
# Copyright:
# Copyright (c) 2018 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.
###############################################################################

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.109326");
  script_version("$Revision: 11337 $");
  script_tag(name:"last_modification", value:"$Date: 2018-09-11 16:23:53 +0200 (Tue, 11 Sep 2018) $");
  script_tag(name:"creation_date", value:"2018-06-15 15:50:18 +0200 (Fri, 15 Jun 2018)");
  script_tag(name:"cvss_base", value:"0.0");
  script_tag(name:"cvss_base_vector", value:"AV:L/AC:H/Au:S/C:N/I:N/A:N");
  script_tag(name:"qod", value:"97");
  script_name('Microsoft Windows: Enable insecure guest logons');
  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (c) 2018 Greenbone Networks GmbH");
  script_family("Policy");
  script_dependencies("smb_reg_service_pack.nasl");
  script_add_preference(name:"Value", type:"radio", value:"0;1");
  script_mandatory_keys("Compliance/Launch");
  script_tag(name:"summary", value:"This test checks the setting for policy
'Enable insecure guest logons' on Windows hosts (at least Windows 7).

The setting determines determines if the SMB client will allow insecure guest
logons to an SMB server.");
  exit(0);
}

include("smb_nt.inc");
include("policy_functions.inc");

if(!get_kb_item("SMB/WindowsVersion")){
  policy_logging(text:'Host is no Microsoft Windows System or it is not possible
to query the registry.');
  exit(0);
}

if(get_kb_item("SMB/WindowsVersion") < "6.1"){
  policy_logging(text:'Host is not at least a Microsoft Windows 7 system.
Older versions of Microsoft Windows are not supported any more.
Please update the system.');
  exit(0);
}

title = 'Enable insecure guest logons';
fixtext = 'Set following UI path accordingly:
Computer Configuration/Administrative Templates/Network/Lanman Workstation/' + title;
type = 'HKLM';
key = 'Software\\Policies\\Microsoft\\Windows\\LanmanWorkstation';
item = 'AllowInsecureGuestAuth';
default = script_get_preference('Value');
value = registry_get_dword(key:key, item:item, type:type);

if(value == ''){
  value = '1';
}

if(int(value) == int(default)){
  compliant = 'yes';
}else{
  compliant = 'no';
}

policy_logging(text:'"' + title + '" is set to: ' + value);
policy_add_oid();
policy_set_dval(dval:default);
policy_fixtext(fixtext:fixtext);
policy_control_name(title:title);
policy_set_kb(val:value);
policy_set_compliance(compliant:compliant);

exit(0);