Nmap NSE net: smb-server-stats

2011-06-01T00:00:00
ID OPENVAS:104058
Type openvas
Reporter NSE-Script: The Nmap Security Scanner; NASL-Wrapper: Greenbone Networks GmbH
Modified 2017-03-06T00:00:00

Description

Attempts to grab the server's statistics over SMB and MSRPC, which uses TCP ports 445 or 139.

An administrator account is required to pull these statistics on most versions of Windows, and Vista and above require UAC to be turned down.

Some of the numbers returned here don't feel right to me, but they're definitely the numbers that Windows returns. Take the values here with a grain of salt.

These statistics are found using a single call to a SRVSVC function, 'NetServerGetStatistics'. This packet is parsed incorrectly by Wireshark, up to version 1.0.3 (and possibly higher).

SYNTAX:

smbbasic: Forces the authentication to use basic security, as opposed to 'extended security'. Against most modern systems, extended security should work, but there may be cases where you want to force basic. There's a chance that you'll get better results for enumerating users if you turn on basic authentication.

smbport: Override the default port choice. If 'smbport' is open, it's used. It's assumed to be the same protocol as port 445, not port 139. Since it probably isn't possible to change Windows' ports normally, this is mostly useful if you're bouncing through a relay or something.

smbsign: Controls whether or not server signatures are checked in SMB packets. By default, on Windows, server signatures aren't enabled or required. By default, this library will always sign packets if it knows how, and will check signatures if the server says to. Possible values are:

  • 'force': Always check server signatures, even if server says it doesn't support them (will probably fail, but is technically more secure).

  • 'negotiate': [default] Use signatures if server supports them.

  • 'ignore': Never check server signatures. Not recommended.

  • 'disable': Don't send signatures, at all, and don't check the server's. not recommended. More information on signatures can be found in 'smbauth.lua'.

randomseed: Set to a value to change the filenames/service names that are randomly generated.

                                        
                                            ###############################################################################
# OpenVAS Vulnerability Test
# $Id: gb_nmap_smb_server_stats_net.nasl 5499 2017-03-06 13:06:09Z teissa $
#
# Autogenerated NSE wrapper
#
# Authors:
# NSE-Script: Ron Bowes
# NASL-Wrapper: autogenerated
#
# Copyright:
# NSE-Script: The Nmap Security Scanner (http://nmap.org)
# Copyright (C) 2011 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_summary = "Attempts to grab the server's statistics over SMB and MSRPC, which uses TCP ports 445 or 139.

An administrator account is required to pull these statistics on most versions of Windows, and Vista
and above require UAC to be turned down.

Some of the numbers returned here don't feel right to me, but they're definitely  the numbers that
Windows returns. Take the values here with a grain of salt.

These statistics are found using a single call to a SRVSVC function,
'NetServerGetStatistics'. This packet is parsed incorrectly by Wireshark, up to version
1.0.3 (and possibly higher).


SYNTAX:

smbbasic:     Forces the authentication to use basic security, as opposed to 'extended security'. 
Against most modern systems, extended security should work, but there may be cases
where you want to force basic. There's a chance that you'll get better results for 
enumerating users if you turn on basic authentication. 


smbport:       Override the default port choice. If 'smbport' is open, it's used. It's assumed
to be the same protocol as port 445, not port 139. Since it probably isn't possible to change
Windows' ports normally, this is mostly useful if you're bouncing through a relay or something. 


smbsign:       Controls whether or not server signatures are checked in SMB packets. By default, on Windows,
server signatures aren't enabled or required. By default, this library will always sign 
packets if it knows how, and will check signatures if the server says to. Possible values are:

- 'force':      Always check server signatures, even if server says it doesn't support them (will 
probably fail, but is technically more secure). 

- 'negotiate': [default] Use signatures if server supports them. 

- 'ignore':    Never check server signatures. Not recommended. 

- 'disable':   Don't send signatures, at all, and don't check the server's. not recommended. 
More information on signatures can be found in 'smbauth.lua'.


randomseed:    Set to a value to change the filenames/service names that are randomly generated.";

if(description)
{
    script_id(104058);
    script_version("$Revision: 5499 $");
    script_tag(name:"last_modification", value:"$Date: 2017-03-06 14:06:09 +0100 (Mon, 06 Mar 2017) $");
    script_tag(name:"creation_date", value:"2011-06-01 16:32:46 +0200 (Wed, 01 Jun 2011)");
    script_tag(name:"cvss_base", value:"4.0");
    script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:S/C:P/I:N/A:N");
    script_name("Nmap NSE net: smb-server-stats");


    script_category(ACT_INIT);
    script_tag(name:"qod_type", value:"remote_analysis");
    script_copyright("NSE-Script: The Nmap Security Scanner; NASL-Wrapper: Greenbone Networks GmbH");
    script_family("Nmap NSE net");
    script_dependencies("nmap_nse_net.nasl");
    script_mandatory_keys("Tools/Launch/nmap_nse_net");

    script_add_preference(name:"smbbasic", value:"", type:"entry");
    script_add_preference(name:"smbport", value:"", type:"entry");
    script_add_preference(name:"smbsign", value:"", type:"entry");
    script_add_preference(name:"randomseed", value:"", type:"entry");

    script_tag(name : "summary" , value : tag_summary);
    exit(0);
}


include("nmap.inc");

# The corresponding NSE script does't belong to the 'safe' category
if (safe_checks()) exit(0);

phase = 0;
if (defined_func("scan_phase")) {
    phase = scan_phase();
}

if (phase == 1) {
    # Get the preferences
    argv = make_array();

    pref = script_get_preference("smbbasic");
    if (!isnull(pref) && pref != "") {
        argv["smbbasic"] = string('"', pref, '"');
    }
    pref = script_get_preference("smbport");
    if (!isnull(pref) && pref != "") {
        argv["smbport"] = string('"', pref, '"');
    }
    pref = script_get_preference("smbsign");
    if (!isnull(pref) && pref != "") {
        argv["smbsign"] = string('"', pref, '"');
    }
    pref = script_get_preference("randomseed");
    if (!isnull(pref) && pref != "") {
        argv["randomseed"] = string('"', pref, '"');
    }
    nmap_nse_register(script:"smb-server-stats", args:argv);
} else if (phase == 2) {
    res = nmap_nse_get_results(script:"smb-server-stats");
    foreach portspec (keys(res)) {
        output_banner = 'Result found by Nmap Security Scanner (smb-server-stats.nse) http://nmap.org:\n\n';
        if (portspec == "0") {
            security_message(data:output_banner + res[portspec], port:0);
        } else {
            v = split(portspec, sep:"/", keep:0);
            proto = v[0];
            port = v[1];
            security_message(data:output_banner + res[portspec], port:port, protocol:proto);
        }
    }
}