author = "jah"
license = "Same as Nmap--See http://nmap.org/book/man-legal.html"
categories = {"discovery", "intrusive"}
description = [[
Attempts to enumerate valid usernames on web servers running with the mod_userdir
module or similar enabled.
The Apache mod_userdir module allows user-specific directories to be accessed
using the http://example.com/~user/ syntax. This script makes http requests in
order to discover valid user-specific directories and infer valid usernames. By
default, the script will use Nmap's
<code>nselib/data/usernames.lst</code>. An HTTP response
status of 200 or 403 means the username is likely a valid one and the username
will be output in the script results along with the status code (in parentheses).
This script makes an attempt to avoid false positives by requesting a directory
which is unlikely to exist. If the server responds with 200 or 403 then the
script will not continue testing it.
CVE-2001-1013: http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2001-1013.
]]
---
-- @args userdir.users The filename of a username list.
-- @args limit The maximum number of users to check.
--
-- @output
-- 80/tcp open http syn-ack Apache httpd 2.2.9
-- |_ apache-userdir-enum: Potential Users: root (403), user (200), test (200)
local http = require 'http'
local shortport = require 'shortport'
local stdnse = require 'stdnse'
local datafiles = require 'datafiles'
portrule = shortport.http
action = function(host, port)
if(not nmap.registry.userdir) then
init()
end
local usernames = nmap.registry.userdir
-- speedy exit if no usernames
if(#usernames == 0) then
if(nmap.debugging() > 0) then
return "Didn't find any users to test (should be in nselib/data/usernames.lst)"
else
return nil
end
end
-- Check what response we get for a 404
local result, result_404, known_404 = http.identify_404(host, port)
if(result == false) then
if(nmap.debugging() > 0) then
return "ERROR: " .. result_404
else
return nil
end
end
-- Check if we can use HEAD requests
local use_head = http.can_use_head(host, port, result_404)
-- Queue up the checks
local all = {}
local i
for i = 1, #usernames, 1 do
if(nmap.registry.args.limit and i > tonumber(nmap.registry.args.limit)) then
stdnse.print_debug(1, "http-userdir-enum.nse: Reached the limit (%d), stopping", nmap.registry.args.limit)
break;
end
if(use_head) then
all = http.pipeline_add("/~" .. usernames[i], nil, all, 'HEAD')
else
all = http.pipeline_add("/~" .. usernames[i], nil, all, 'GET')
end
end
local results = http.pipeline_go(host, port, all)
-- Check for http.pipeline error
if(results == nil) then
stdnse.print_debug(1, "http-userdir-enum.nse: http.pipeline returned nil")
if(nmap.debugging() > 0) then
return "ERROR: http.pipeline returned nil"
else
return nil
end
end
local found = {}
for i, data in pairs(results) do
if(http.page_exists(data, result_404, known_404, "/~" .. usernames[i], true)) then
stdnse.print_debug(1, "http-userdir-enum.nse: Found a valid user: %s", usernames[i])
table.insert(found, usernames[i])
end
end
if(#found > 0) then
return string.format("Potential Users: %s", table.concat(found, ", "))
elseif(nmap.debugging() > 0) then
return "Didn't find any users!"
end
return nil
end
---
-- Parses a file containing usernames (1 per line), defaulting to
-- "nselib/data/usernames.lst" and stores the resulting array of usernames in
-- the registry for use by all threads of this script. This means file access
-- is done only once per Nmap invocation. init() also adds a random string to
-- the array (in the first position) to attempt to catch false positives.
-- @return nil
function init()
local customlist = nmap.registry.args.users or
(nmap.registry.args.userdir and nmap.registry.args.userdir.users) or
nmap.registry.args['userdir.users']
local read, usernames = datafiles.parse_file(customlist or "nselib/data/usernames.lst", {})
if not read then
stdnse.print_debug(1, "%s %s", SCRIPT_NAME,
usernames or "Unknown Error reading usernames list.")
nmap.registry.userdir = {}
return nil
end
-- random dummy username to catch false positives (not necessary)
-- if #usernames > 0 then table.insert(usernames, 1, randomstring()) end
nmap.registry.userdir = usernames
stdnse.print_debug(1, "%s Testing %d usernames.", SCRIPT_NAME, #usernames)
return nil
end
---
-- Uses openssl.rand_pseudo_bytes (if available, os.time() if not) and base64.enc
-- to produce a randomish string of at least 11 alphanumeric chars.
-- @return String
function randomstring()
local bin = require"bin"
local base64 = require"base64"
local rnd, s, l, _
if pcall(require, "openssl") then
rnd = openssl.rand_pseudo_bytes
end
s = rnd and rnd(8) or tostring( os.time() )
-- increase the length of the string by 0 to 7 chars
_, l = bin.unpack(">C", s, 8) -- eighth byte should be safe for os.time() too
s = l%8 > 0 and s .. s:sub(1,l%8) or s
-- base 64 encode and replace any non alphanum chars (with 'n' for nmap!)
s = base64.enc(s):sub(1,-2):gsub("%W", "n")
return s
end
Copyright 2K16 - 2K18 Indonesian Hacker Rulez