152 lines
4.0 KiB
Lua

local brute = require "brute"
local creds = require "creds"
local nmap = require "nmap"
local shortport = require "shortport"
local stdnse = require "stdnse"
local string = require "string"
local openssl = stdnse.silent_require "openssl"
description = [[
Performs brute force password auditing against an Nping Echo service.
See https://nmap.org/book/nping-man-echo-mode.html for Echo Mode
documentation.
]]
---
-- @usage
-- nmap -p 9929 --script nping-brute <target>
--
-- @output
-- 9929/tcp open nping-echo
-- | nping-brute:
-- | Accounts
-- | 123abc => Valid credentials
-- | Statistics
-- |_ Perfomed 204 guesses in 204 seconds, average tps: 1
author = "Toni Ruottu"
license = "Same as Nmap--See https://nmap.org/book/man-legal.html"
categories = {"brute", "intrusive"}
portrule = shortport.port_or_service(9929, "nping-echo")
local function readmessage(socket, length)
local msg = ""
while #msg < length do
local status, tmp = socket:receive_bytes(1)
if not status then
return nil
end
msg = msg .. tmp
end
return msg
end
Driver =
{
NEP_VERSION = 0x01,
AES_128_CBC = "aes-128-cbc",
SHA256 = "sha256",
new = function(self, host, port)
local o = {}
setmetatable(o, self)
self.__index = self
o.host = host
o.port = port
return o
end,
nepkey = function(self, password, nonce, typeid)
local seed = password .. nonce .. typeid
local h = openssl.digest(self.SHA256, seed)
for i = 1, 1000 do
h = openssl.digest(self.SHA256, h)
end
return string.unpack("c16", h)
end,
getservernonce = function(self, serverhs)
local offset = 63 -- 63 bytes of header before the nonce
return serverhs:sub(offset+1, offset+4)
end,
chsbody = function(self)
local IP4 = "\x04"
local IP6 = "\x06"
local family = IP6
local target = self.host.bin_ip
if #target == 4 then
target = target .. ("\0"):rep(12)
family = IP4
end
return target .. family .. ("\0"):rep(15)
end,
clienths = function(self, snonce, password)
local NEP_HANDSHAKE_CLIENT = 0x02
local NEP_HANDSHAKE_CLIENT_LEN = 36
local NEP_CLIENT_CIPHER_ID = "NEPkeyforCiphertextClient2Server"
local NEP_CLIENT_MAC_ID = "NEPkeyforMACClient2Server"
local now = nmap.clock()
local seqb = openssl.rand_bytes(4)
local cnonce = openssl.rand_bytes(32)
local nonce = snonce .. cnonce
local enckey = self:nepkey(password, nonce, NEP_CLIENT_CIPHER_ID)
local mackey = self:nepkey(password, nonce, NEP_CLIENT_MAC_ID)
local iv = string.unpack("c16", cnonce)
local plain = self:chsbody()
local crypted = openssl.encrypt(self.AES_128_CBC, enckey, iv, plain)
local head = string.pack(">BB I2 c4 I4 x4", self.NEP_VERSION, NEP_HANDSHAKE_CLIENT, NEP_HANDSHAKE_CLIENT_LEN, seqb, now) .. nonce
local mac = openssl.hmac(self.SHA256, mackey, head .. plain)
return head .. crypted .. mac
end,
testpass = function(self, password)
local SERVERHS_LEN = 96
local FINALHS_LEN = 112
local serverhs = readmessage(self.socket, SERVERHS_LEN)
if serverhs == nil then
return false
end
local snonce = self:getservernonce(serverhs)
local response = self:clienths(snonce, password)
self.socket:send(response)
local finalhs = readmessage(self.socket, FINALHS_LEN)
if finalhs == nil then
return false
end
return true
end,
connect = function(self)
self.socket = brute.new_socket()
return self.socket:connect(self.host, self.port)
end,
login = function(self, _, password)
if self:testpass(password) then
return true, creds.Account:new("", password, creds.State.VALID)
end
return false, brute.Error:new("Incorrect password")
end,
disconnect = function(self)
return self.socket:close()
end,
}
action = function(host, port)
local engine = brute.Engine:new(Driver, host, port)
engine.options.firstonly = true
engine.options:setOption("passonly", true)
engine.options.script_name = SCRIPT_NAME
local status, result = engine:start()
return result
end