local brute = require "brute"
local creds = require "creds"
local http = require "http"
local nmap = require "nmap"
local shortport = require "shortport"
local stdnse = require "stdnse"
local table = require "table"
local url = require "url"
description = [[
Performs brute force password auditing against http form-based authentication.
]]
---
-- @usage
-- nmap --script http-form-brute -p 80 <host>
--
-- This script uses the unpwdb and brute libraries to perform password
-- guessing. Any successful guesses are stored in the nmap registry, under
-- the nmap.registry.credentials.http key for other scripts to use.
--
-- The script automatically attempts to discover the form field names to
-- use in order to perform password guessing. If it fails doing so the form
-- parameters can be supplied using the uservar and passvar arguments.
--
-- After attempting to authenticate using a HTTP POST request the script
-- analyzes the response and attempt to determine whether authentication was
-- successful or not. The script analyzes this by checking the response using
-- the following rules:
-- 1. If the response was empty the authentication was successful
-- 2. If the response contains the message passed in the onsuccess
-- argument the authentication was successful
-- 3. If no onsuccess argument was passed, and if the response
-- does not contain the message passed in the onfailure argument the
-- authentication was successful
-- 4. If neither the onsuccess or onfailure argument was passed and the
-- response does not contain a password form field authentication
-- was successful
-- 5. Authentication failed
--
-- @output
-- PORT STATE SERVICE REASON
-- 80/tcp open http syn-ack
-- | http-brute:
-- | Accounts
-- | Patrik Karlsson:secret => Login correct
-- | Statistics
-- |_ Perfomed 60023 guesses in 467 seconds, average tps: 138
--
-- Summary
-- -------
-- x The Driver class contains the driver implementation used by the brute
-- library
--
-- @args http-form-brute.path points to the path protected by authentication
-- @args http-form-brute.hostname sets the host header in case of virtual
-- hosting
-- @args http-form-brute.uservar (optional) sets the http-variable name that
-- holds the username used to authenticate. A simple autodetection of
-- this variable is attempted.
-- @args http-form-brute.passvar sets the http-variable name that holds the
-- password used to authenticate. A simple autodetection of this variable
-- is attempted.
-- @args http-form-brute.onsuccess (optional) sets the message to expect on
-- successful authentication
-- @args http-form-brute.onfailure (optional) sets the message to expect on
-- unsuccessful authentication
--
-- Version 0.3
-- Created 07/30/2010 - v0.1 - created by Patrik Karlsson <patrik@cqure.net>
-- Revised 05/23/2011 - v0.2 - changed so that uservar is optional
-- Revised 06/05/2011 - v0.3 - major re-write, added onsucces, onfailure and
-- support for redirects
--
author = "Patrik Karlsson"
license = "Same as Nmap--See http://nmap.org/book/man-legal.html"
categories = {"intrusive", "brute"}
portrule = shortport.port_or_service( {80, 443}, {"http", "https"}, "tcp", "open")
local form_params = {}
Driver = {
new = function(self, host, port, options)
local o = {}
setmetatable(o, self)
self.__index = self
o.host = nmap.registry.args['http-form-brute.hostname'] or host
o.port = port
o.options = options
return o
end,
connect = function( self )
-- This will cause problems, as ther is no way for us to "reserve"
-- a socket. We may end up here early with a set of credentials
-- which won't be guessed until the end, due to socket exhaustion.
return true
end,
login = function( self, username, password )
-- we need to supply the no_cache directive, or else the http library
-- incorrectly tells us that the authentication was successfull
local postparams = { [self.options.passvar] = password }
if ( self.options.uservar ) then postparams[self.options.uservar] = username end
local response = Driver.postRequest(self.host, self.port, self.options.path, postparams)
local success = false
-- if we have no response, we were successful
if ( not(response.body) ) then
success = true
-- if we have a response and it matches our onsuccess match, login was successful
elseif ( response.body and
self.options.onsuccess and
response.body:match(self.options.onsuccess) ) then
success = true
-- if we have a response and it does not match our onfailure, login was successful
elseif ( response.body and
not(self.options.onsuccess) and
self.options.onfailure and
not(response.body:match(self.options.onfailure))) then
success = true
-- if we have a response and no onfailure or onsuccess match defined
-- and can't find a password field, login was successful
elseif ( response.body and
not(self.options.onfailure) and
not(self.options.onsuccess) and
not(response.body:match("input.-type=[\"]*[Pp][Aa][Ss][Ss][Ww][Oo][Rr][Dd][\"]*"))
) then
success = true
end
-- We check whether the body was empty or that we have a body without our user- and pass-var
if ( success ) then
nmap.registry['credentials'] = nmap.registry['credentials'] or {}
nmap.registry.credentials['http'] = nmap.registry.credentials['http'] or {}
table.insert( nmap.registry.credentials.http, { username = username, password = password } )
return true, brute.Account:new( username, password, creds.State.VALID)
end
return false, brute.Error:new( "Incorrect password" )
end,
disconnect = function( self )
return true
end,
check = function( self )
return true
end,
postRequest = function( host, port, path, options )
local response = http.post( host, port, path, { no_cache = true }, nil, options )
local status = ( response and tonumber(response.status) ) or 0
if ( status > 300 and status < 400 ) then
local new_path = url.absolute(path, response.header.location)
response = http.get( host, port, new_path, { no_cache = true } )
end
return response
end,
}
--- Attempts to auto-detect known form-fields
--
local function detectFormFields( host, port, path )
local response = http.get( host, port, path )
local user_field, pass_field
if ( response.status == 200 ) then
user_field = response.body:match("<[Ii][Nn][Pp][Uu][Tt].-name=[\"]*([^\"]-[Uu][Ss][Ee][Rr].-)[\"]*.->")
pass_field = response.body:match("<[Ii][Nn][Pp][Uu][Tt].-name=[\"]*([Pp][Aa][Ss][Ss].-)[\"]*.->")
if ( not(pass_field) ) then
pass_field = response.body:match("<[Ii][Nn][Pp][Uu][Tt].-name=[\"]-([^\"]-[Kk][Ee][Yy].-)[\"].->")
end
end
return user_field, pass_field
end
action = function( host, port )
local uservar = stdnse.get_script_args('http-form-brute.uservar')
local passvar = stdnse.get_script_args('http-form-brute.passvar')
local path = stdnse.get_script_args('http-form-brute.path') or "/"
local onsuccess = stdnse.get_script_args("http-form-brute.onsuccess")
local onfailure = stdnse.get_script_args("http-form-brute.onfailure")
local _
-- if now fields were given attempt to autodetect
if ( not(uservar) and not(passvar) ) then
uservar, passvar = detectFormFields( host, port, path )
-- if now passvar was detected attempt to autodetect
elseif ( not(passvar) ) then
_, passvar = detectFormFields( host, port, path )
end
-- uservar is optional, so only make sure we have a passvar
if ( not( passvar ) ) then
return "\n ERROR: No passvar was specified (see http-form-brute.passvar)"
end
if ( not(path) ) then
return "\n ERROR: No path was specified (see http-form-brute.path)"
end
if ( onsuccess and onfailure ) then
return "\n ERROR: Either the onsuccess or onfailure argument should be passed, not both."
end
local options = { [passvar] = "this_is_not_a_valid_password" }
if ( uservar ) then options[uservar] = "this_is_not_a_valid_user" end
local response = Driver.postRequest( host, port, path, options )
if ( not(response) or not(response.body) or response.status ~= 200 ) then
return ("\n ERROR: Failed to retrieve path (%s) from server"):format(path)
end
-- try to detect onfailure match
if ( onfailure and not(response.body:match(onfailure)) ) then
return ("\n ERROR: Failed to match password failure message (%s)"):format(onfailure)
elseif ( not(onfailure) and
not(onsuccess) and
not(response.body:match("input.-type=[\"]*[Pp][Aa][Ss][Ss][Ww][Oo][Rr][Dd][\"]*")) ) then
return ("\n ERROR: Failed to detect password form field see (http-form-brute.onsuccess or http-form-brute.onfailure)")
end
local engine = brute.Engine:new( Driver, host, port, {
uservar = uservar, passvar = passvar,
path = path, onsuccess = onsuccess, onfailure = onfailure
}
)
-- there's a bug in http.lua that does not allow it to be called by
-- multiple threads
engine:setMaxThreads(1)
engine.options.script_name = SCRIPT_NAME
if ( not(uservar) ) then
engine.options:setOption( "passonly", true )
end
local status, result = engine:start()
return result
end
@KyuuKazami