Nmap smb-enum-shares NSE Script


This page contains detailed information about how to use the smb-enum-shares NSE script. For list of all NSE scripts, visit the Nmap NSE Library.

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Script Overview

Script source code: https://github.com/nmap/nmap/tree/master/scripts/smb-enum-shares.nse
Script categories: discovery, intrusive
Target service / protocol: smb, netbios, tcp, udp
Target network port(s): 137, 139, 445
List of CVEs: -

Script Description

The smb-enum-shares.nse script attempts to list shares using the srvsvc.NetShareEnumAll MSRPC function and retrieve more information about them using srvsvc.NetShareGetInfo. If access to those functions is denied, a list of common share names are checked.

Finding open shares is useful to a penetration tester because there may be private files shared, or, if it's writable, it could be a good place to drop a Trojan or to infect a file that's already there. Knowing where the share is could make those kinds of tests more useful, except that determining where the share is requires administrative privileges already.

Running NetShareEnumAll will work anonymously against Windows 2000, and requires a user-level account on any other Windows version. Calling NetShareGetInfo requires an administrator account on all versions of Windows up to 2003, as well as Windows Vista and Windows 7, if UAC is turned down.

Even if NetShareEnumAll is restricted, attempting to connect to a share will always reveal its existence. So, if NetShareEnumAll fails, a pre-generated list of shares, based on a large test network, are used. If any of those succeed, they are recorded.

After a list of shares is found, the script attempts to connect to each of them anonymously, which divides them into "anonymous", for shares that the NULL user can connect to, or "restricted", for shares that require a user account.

Smb-enum-shares NSE Script Arguments

This is a full list of arguments supported by the smb-enum-shares.nse script:

smbdomain

The domain to log in with. If you aren't in a domain environment, then anything will (should?) be accepted by the server.

smbhash

A password hash to use when logging in. This is given as a single hex string (32 characters) or a pair of hex strings (both 32 characters, optionally separated by a single character). These hashes are the LanMan or NTLM hash of the user's password, and are stored on disk or in memory. They can be retrieved from memory using the fgdump or pwdump tools.

smbnoguest

Use to disable usage of the 'guest' account.

smbpassword

The password to connect with. Be cautious with this, since some servers will lock accounts if the incorrect password is given. Although it's rare that the Administrator account can be locked out, in the off chance that it can, you could get yourself in trouble. To use a blank password, leave this parameter off altogether.

smbtype

The type of SMB authentication to use. These are the possible options:

  • v1: Sends LMv1 and NTLMv1.
  • LMv1: Sends LMv1 only.
  • NTLMv1: Sends NTLMv1 only (default).
  • v2: Sends LMv2 and NTLMv2.
  • LMv2: Sends LMv2 only.
  • NTLMv2: Doesn't exist; the protocol doesn't support NTLMv2 alone. The default, NTLMv1, is a pretty decent compromise between security and compatibility. If you are paranoid, you might want to use v2 or lmv2 for this. (Actually, if you're paranoid, you should be avoiding this protocol altogether!). If you're using an extremely old system, you might need to set this to v1 or lm, which are less secure but more compatible. For information, see smbauth.lua.

smbusername

The SMB username to log in with. The forms "DOMAIN\username" and "username@DOMAIN" are not understood. To set a domain, use the smbdomain argument.

randomseed

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

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.

- - -
To use these script arguments, add them to the Nmap command line using the --script-args arg1=value,[arg2=value,..] syntax. For example:

nmap --script=smb-enum-shares --script-args smbdomain=value,smbhash=value <target>

Smb-enum-shares NSE Script Example Usage

Here's an example of how to use the smb-enum-shares.nse script:

nmap --script smb-enum-shares.nse -p445 <host>

sudo nmap -sU -sS --script smb-enum-shares.nse -p U:137,T:139 <host>

Smb-enum-shares NSE Script Example Output

Here's a sample output from the smb-enum-shares.nse script:

Host script results:
| smb-enum-shares:
|  account_used: WORKGROUP\Administrator
|  ADMIN$
|    Type: STYPE_DISKTREE_HIDDEN
|    Comment: Remote Admin
|    Users: 0
|    Max Users: <unlimited>
|    Path: C:\WINNT
|    Anonymous access: <none>
|    Current user access: READ/WRITE
|  C$
|    Type: STYPE_DISKTREE_HIDDEN
|    Comment: Default share
|    Users: 0
|    Max Users: <unlimited>
|    Path: C:\
|    Anonymous access: <none>
|    Current user access: READ
|  IPC$
|    Type: STYPE_IPC_HIDDEN
|    Comment: Remote IPC
|    Users: 1
|    Max Users: <unlimited>
|    Path:
|    Anonymous access: READ
|_   Current user access: READ

Smb-enum-shares NSE Script Example XML Output

Here's a sample XML output from the smb-enum-shares.nse script produced by providing the -oX <file> Nmap option:

 <elem key="account_used">WORKGROUP\Administrator</elem>
 <table key="ADMIN$">
   <elem key="Type">STYPE_DISKTREE_HIDDEN</elem>
   <elem key="Comment">Remote Admin</elem>
   <elem key="Users">0</elem>
   <elem key="Max Users"><unlimited></elem>
   <elem key="Path">C:\WINNT</elem>
   <elem key="Anonymous access"><none></elem>
   <elem key="Current user access">READ/WRITE</elem>
 </table>
 <table key="C$">
   <elem key="Type">STYPE_DISKTREE_HIDDEN</elem>
   <elem key="Comment">Default share</elem>
   <elem key="Users">0</elem>
   <elem key="Max Users"><unlimited></elem>
   <elem key="Path">C:\</elem>
   <elem key="Anonymous access"><none></elem>
   <elem key="Current user access">READ</elem>
 </table>
 <table key="IPC$">
   <elem key="Type">STYPE_IPC_HIDDEN</elem>
   <elem key="Comment">Remote IPC</elem>
   <elem key="Users">1</elem>
   <elem key="Max Users"><unlimited></elem>
   <elem key="Path"></elem>
   <elem key="Anonymous access">READ</elem>
   <elem key="Current user access">READ</elem>
 </table>

Author

  • Ron Bowes

References

See Also

Related NSE scripts to the smb-enum-shares.nse script:

Visit Nmap NSE Library for more scripts.

The smb-enum-shares.nse script may fail with the following error messages. Check for the possible causes by using the code snippets highlighted below found in the script source code. This can often times help in identifying the root cause of the problem.

Couldn't enumerate shares: %s

Here is a relevant code snippet related to the "Couldn't enumerate shares: %s" error message:

107:	  local response = stdnse.output_table()
108:	
109:	  -- Get the list of shares
110:	  status, shares, extra = smb.share_get_list(host)
111:	  if(status == false) then
112:	    return stdnse.format_output(false, string.format("Couldn't enumerate shares: %s", shares))
113:	  end
114:	
115:	  if(extra ~= nil and extra ~= '') then
116:	    response.note = extra
117:	  end

warning'] = string.format("Couldn't get details for share: %s", share['details

Here is a relevant code snippet related to the "warning'] = string.format("Couldn't get details for share: %s", share['details" error message:

134:	  for i = 1, #shares, 1 do
135:	    local share = shares[i]
136:	    local share_output = stdnse.output_table()
137:	
138:	    if(type(share['details']) ~= 'table') then
139:	      share_output['warning'] = string.format("Couldn't get details for share: %s", share['details'])
140:	      -- A share of 'NT_STATUS_OBJECT_NAME_NOT_FOUND' indicates this isn't a fileshare
141:	      if(share['user_can_write'] == "NT_STATUS_OBJECT_NAME_NOT_FOUND") then
142:	        share_output["Type"] = "Not a file share"
143:	      else
144:	        table.insert(host.registry['smb_shares'], share.name)

Version

This page has been created based on Nmap version 7.92.

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