nmap脚本详解

nmap --script

前言

我们通过nmap script来大幅扩展nmap的功能，nmap具有强大的脚本引擎NSE（Nmap Scripting Engine），它允许用户编写（和共享）简单的脚本（使用lua编程语言）自动化各种网络任务

官方文档

NSEDoc Reference Portal — Nmap Scripting Engine documentation

目前nmap官方有604个NSE脚本，安装nmap后存储在script文件夹下，这些都是Nmap特有的，是基于lua语言编写的

nmap脚本分类

nmap脚本主要分为以下几类，在扫描时可根据需要设置--script=类别这种方式进行比较笼统的扫描：

auth: 负责处理鉴权证书（绕开鉴权）的脚本

broadcast: 在局域网内探查更多服务开启状况，如dhcp/dns/sqlserver等服务

brute: 提供暴力破解方式，针对常见的应用如http/snmp等

default: 使用-sC或-A选项扫描时候默认的脚本，提供基本脚本扫描能力

discovery: 对网络进行更多的信息，如SMB枚举、SNMP查询等

dos: 用于进行拒绝服务攻击

exploit: 利用已知的漏洞入侵系统

external: 利用第三方的数据库或资源，例如进行whois解析

fuzzer: 模糊测试的脚本，发送异常的包到目标机，探测出潜在漏洞 intrusive: 入侵性的脚本，此类脚本可能引发对方的IDS/IPS的记录或屏蔽

malware: 探测目标机是否感染了病毒、开启了后门等信息

safe: 此类与intrusive相反，属于安全性脚本

version: 负责增强服务与版本扫描（Version Detection）功能的脚本

vuln: 负责检查目标机是否有常见的漏洞（Vulnerability），如是否有MS08_067

使用方式

指定运行脚本

当我们使用Nmap并添加参数-sC或者--script时，Nmap会执行NSE脚本

例如，在script目录下有http-title.nse、http-trace.nse脚本，执行如下命令：

nmap --script http-title scanme.nmap.org

传递参数

--script-args=key1=value1,key2=value2...

从文件中读取参数

–script-args-file=filename

显示全部发送和收到的数据

--script-trace

更新数据库

在Nmap的scripts目录里有一个script.db，该文件中保存了当前Nmap可用的脚本，类似于一个小型数据库，如果我们开启nmap并且调用了此参数，则nmap会自行扫描scripts目录中的扩展脚本，进行数据库更新

--script-updatedb

脚本帮助

指定对应的脚本信息，Nmap会输出该脚本名称对应的脚本使用参数，以及详细介绍信息。

--script-help=脚本名称

nmap脚本简介

一个NSE脚本的书写一般分为四步：

导入脚本编写所需库
编写脚本描述信息
确定Rule类型
编写Action

Nmap nse脚本模板结构图

其中Rule存在四种类型：

Prerule 在Nmap没有扫描之前进行触发
Hostrule 在Nmap执行主机发现或探测时进行触发
Protrule 在Nmap执行端口扫描的时候触发
Postrule 在Nmap结束的时候触发脚本，通常用于扫描结果的数据提取和整理

用于描述脚本的触发规则，返回值只有true和false两种。返回值决定了后面的action对应的函数是否执行

true - 执行
false - 不执行

在我看来

Rule描述脚本的触发规则，定义了脚本在nmap生命周期的啥时候来执行

我们选择 http-php-version.nse脚本来跟进分析一下，这个脚本的主要作用是检测PHP服务器的版本

查看API手册 https://nmap.org/nsedoc/lib/ 来导入你要导入的lua脚本 - nmap内置模块

local http = require "http"

local nmap = require "nmap"

local shortport = require "shortport"

local stdnse = require "stdnse"

local string = require "string"

local table = require "table"

local openssl = stdnse.silent_require "openssl"

description对脚本进行概述

description = [[

Attempts to retrieve the PHP version from a web server. PHP has a number

of magic queries that return images or text that can vary with the PHP

version. This script uses the following queries:

* <code>/?=PHPE9568F36-D428-11d2-A769-00AA001ACF42</code>: gets a GIF logo, which changes on April Fool's Day.

* <code>/?=PHPB8B5F2A0-3C92-11d3-A3A9-4C7B08C10000</code>: gets an HTML credits page.

A list of magic queries is at http://www.0php.com/php_easter_egg.php.

The script also checks if any header field value starts with

<code>"PHP"</code> and reports that value if found.

PHP versions after 5.5.0 do not respond to these queries.

Link:

* http://phpsadness.com/sad/11

]]

作者和脚本分类

author = {"Ange Gutek", "Rob Nicholls"}

license = "Same as Nmap--See https://nmap.org/book/man-legal.html"

categories = {"discovery", "safe"}

在端口扫描的时候运行判断函数，这里直接调用了shortport提供的判断

portrule = shortport.http

然后定义了访问的接口和PHP对应关系

-- These are the magic queries that return fingerprintable data.

local LOGO_QUERY = "/?=PHPE9568F36-D428-11d2-A769-00AA001ACF42"

local CREDITS_QUERY = "/?=PHPB8B5F2A0-3C92-11d3-A3A9-4C7B08C10000"

-- For PHP 5.x hashes up to 5.2.14 and 5.3.3 see:

-- http://seclists.org/nmap-dev/2010/q4/518

local LOGO_HASHES = {

  -- Bunny (Carmella)

  ["37e194b799d4aaff10e39c4e3b2679a2"] = {"5.0.0 - 5.0.3"},

  -- Black Scottish Terrier (Scotch)

  ["4b2c92409cf0bcf465d199e93a15ac3f"] = {"4.3.11", "4.4.0 - 4.4.9", "5.0.4 - 5.0.5", "5.1.0 - 5.1.2"},

  -- Colored

  ["50caaf268b4f3d260d720a1a29c5fe21"] = {"5.1.3 - 5.1.6", "5.2.0 - 5.2.17"},

  -- PHP Code Guy With Breadsticks (Thies C. Arntzen)

  ["85be3b4be7bfe839cbb3b4f2d30ff983"] = {"4.0.0 - 4.2.3"},

  -- Brown Dog In Grass (Nadia)

  ["a57bd73e27be03a62dd6b3e1b537a72c"] = {"4.3.0 - 4.3.11"},

  -- Elephant

  ["fb3bbd9ccc4b3d9e0b3be89c5ff98a14"] = {"5.3.0 - 5.3.29", "5.4.0 - 5.4.45"},

}

local CREDITS_HASHES = {

  ["744aecef04f9ed1bc39ae773c40017d1"] = {"4.0.1pl2", "4.1.0 - 4.1.2", "4.2.2"},

  ["4ba58b973ecde12dafbbd40b54afac43"] = {"4.1.1 OpenVMS"},

  ["8bc001f58bf6c17a67e1ca288cb459cc"] = {"4.2.0 - 4.2.2"},

  ["3422eded2fcceb3c89cabb5156b5d4e2"] = {"4.2.3"},

  ["1e04761e912831dd29b7a98785e7ac61"] = {"4.3.0"},

  ["1e04761e912831dd29b7a98785e7ac61"] = {"4.3.1"},

  ["65eaaaa6c5fdc950e820f9addd514b8b"] = {"4.3.1 Mandrake Linux"},

  ["8a8b4a419103078d82707cf68226a482"] = {"4.3.2"},

  ["22d03c3c0a9cff6d760a4ba63909faea"] = {"4.3.2"}, -- entity encoded "'"

  ["8a4a61f60025b43f11a7c998f02b1902"] = {"4.3.3 - 4.3.5"},

  ["39eda6dfead77a33cc6c63b5eaeda244"] = {"4.3.3 - 4.3.5"}, -- entity encoded "'"

  ["913ec921cf487109084a518f91e70859"] = {"4.3.6 - 4.3.8"},

  ["884ba1f11e0e956c7c3ba64e5e33ee9f"] = {"4.3.6 - 4.3.8"}, -- entity encoded

  ["c5fa6aec2cf0172a5a1df7082335cf9e"] = {"4.3.8 Mandrake Linux"},

  ["8fbf48d5a2a64065fc26db3e890b9871"] = {"4.3.9 - 4.3.11"},

  ["f9b56b361fafd28b668cc3498425a23b"] = {"4.3.9 - 4.3.11"}, -- entity encoded "'"

  ["ddf16ec67e070ec6247ec1908c52377e"] = {"4.4.0"},

  ["3d7612c9927b4c5cfff43efd27b44124"] = {"4.4.0"}, -- entity encoded "'"

  ["55bc081f2d460b8e6eb326a953c0e71e"] = {"4.4.1"},

  ["bed7ceff09e9666d96fdf3518af78e0e"] = {"4.4.2 - 4.4.4"},

  ["692a87ca2c51523c17f597253653c777"] = {"4.4.5 - 4.4.7"},

  ["50ac182f03fc56a719a41fc1786d937d"] = {"4.4.8 - 4.4.9"},

  ["3c31e4674f42a49108b5300f8e73be26"] = {"5.0.0 - 5.0.5"},

  ["e54dbf41d985bfbfa316dba207ad6bce"] = {"5.0.0"},

  ["6be3565cdd38e717e4eb96868d9be141"] = {"5.0.5"},

  ["b7cf53972b35b5d57f12c9d857b6b507"] = {"5.0.5 ActiveScript"},

  ["5518a02af41478cfc492c930ace45ae5"] = {"5.1.0 - 5.1.1"},

  ["6cb0a5ba2d88f9d6c5c9e144dd5941a6"] = {"5.1.2"},

  ["82fa2d6aa15f971f7dadefe4f2ac20e3"] = {"5.1.3 - 5.1.6"},

  ["6a1c211f27330f1ab602c7c574f3a279"] = {"5.2.0"},

  ["d3894e19233d979db07d623f608b6ece"] = {"5.2.1"},

  ["56f9383587ebcc94558e11ec08584f05"] = {"5.2.2"},

  ["c37c96e8728dc959c55219d47f2d543f"] = {"5.2.3 - 5.2.5", "5.2.6RC3"},

  ["1776a7c1b3255b07c6b9f43b9f50f05e"] = {"5.2.6"},

  ["1ffc970c5eae684bebc0e0133c4e1f01"] = {"5.2.7 - 5.2.8"},

  ["54f426521bf61f2d95c8bfaa13857c51"] = {"5.2.9 - 5.2.14"},

  ["adb361b9255c1e5275e5bd6e2907c5fb"] = {"5.2.15 - 5.2.17"},

  ["db23b07a9b426d0d033565b878b1e384"] = {"5.3.0"},

  ["a4c057b11fa0fba98c8e26cd7bb762a8"] = {"5.3.1 - 5.3.2"},

  ["b34501471d51cebafacdd45bf2cd545d"] = {"5.3.3"},

  ["e3b18899d0ffdf8322ed18d7bce3c9a0"] = {"5.3.4 - 5.3.5"},

  ["2e7f5372931a7f6f86786e95871ac947"] = {"5.3.6"},

  ["f1f1f60ac0dcd700a1ad30aa81175d34"] = {"5.3.7 - 5.3.8"},

  ["23f183b78eb4e3ba8b3df13f0a15e5de"] = {"5.3.9 - 5.3.29"},

  ["85da0a620fabe694dab1d55cbf1e24c3"] = {"5.4.0 - 5.4.14"},

  ["ebf6d0333d67af5f80077438c45c8eaa"] = {"5.4.15 - 5.4.45"},

}

最后就是判定的主要逻辑了，虽然我们不懂Lua，但是我们还是能大概看懂这里做的事情

action = function(host, port)

  local response

  local logo_versions, credits_versions

  local logo_hash, credits_hash

  local header_name, header_value

  local lines

  -- 1st pass : the "special" PHP-logo test

  response = http.get(host, port, LOGO_QUERY)

  if response.body and response.status == 200 then

    logo_hash = stdnse.tohex(openssl.md5(response.body))

    logo_versions = LOGO_HASHES[logo_hash]

  end

  -- 2nd pass : the PHP-credits test

  response = http.get(host, port, CREDITS_QUERY)

  if response.body and response.status == 200 then

    credits_hash = stdnse.tohex(openssl.md5(response.body))

    credits_versions = CREDITS_HASHES[credits_hash]

  end

  for name, value in pairs(response.header) do

    if string.match(value, "^PHP/") then

      header_name = name

      header_value = value

      break

    end

  end

  lines = {}

  if logo_versions then

    lines[#lines + 1] = "Versions from logo query (less accurate): " .. table.concat(logo_versions, ", ")

  elseif logo_hash and nmap.verbosity() >= 2 then

    lines[#lines + 1] = "Logo query returned unknown hash " .. logo_hash

  end

  if credits_versions then

    lines[#lines + 1] = "Versions from credits query (more accurate): " .. table.concat(credits_versions, ", ")

  elseif credits_hash and nmap.verbosity() >= 2 then

    lines[#lines + 1] = "Credits query returned unknown hash " .. credits_hash

  end

  if header_name and header_value then

    lines[#lines + 1] = "Version from header " .. header_name .. ": " .. header_value

  end

  if #lines > 0 then

    return table.concat(lines, "\n")

  end

end

访问可能存在泄露PHP版本的接口，并将返回值进行md5计算，检查字典里是否有对应值，如果有的话就说明存在PHP的版本泄露，最后返回结果。

事实上只是实现的语言不一样，核心的检测原理都是一致的

按照应用服务扫描

nmap脚本的完整文档可以看官方文档 https://nmap.org/nsedoc/scripts/

下面是常用的一些应用扫描

VNC扫描

VNC (Virtual Network Console)是虚拟网络控制台的缩写。它是一款优秀的远程控制工具软件

检查vnc bypass

nmap  --script=realvnc-auth-bypass 192.168.137.4

检查vnc认证方式

nmap  --script=vnc-auth  192.168.137.4

获取vnc信息

nmap  --script=vnc-info  192.168.137.4

smb扫描

SMB(全称是Server Message Block)是一个网络协议名，它能被用于Web连接和客户端与服务器之间的信息沟通

smb破解

nmap  --script=smb-brute.nse 192.168.137.4

smb字典破解

nmap --script=smb-brute.nse --script-args=userdb=/var/passwd,passdb=/var/passwd 192.168.137.4

smb漏洞检测

nmap  --script=smb-check-vulns.nse --script-args=unsafe=1 192.168.137.4

Mssql扫描

暴力破解用户名密码

nmap -p1433 --script=ms-sql-brute --script-args=userdb=/var/passwd,passdb=/var/passwd 192.168.137.4

有密码后xp_cmdshell执行命令

nmap -p 1433 --script ms-sql-xp-cmdshell --script-args mssql.username=sa,mssql.password=sa,ms-sql-xp-cmdshell.cmd="net user" 192.168.137.4

有密码后dymphash

nmap -p 1433 --script ms-sql-dump-hashes.nse --script-args mssql.username=sa,mssql.password=sa  192.168.137.4

Mysql扫描

扫描root空口令

nmap -p3306 --script=mysql-empty-password.nse 192.168.137.4

列举所有mysql用户

nmap -p3306 --script=mysql-users.nse --script-args=mysqluser=root 192.168.137.4

扫描mysql相关的脚本

nmap --script=mysql-* 192.168.137.4

Oracle扫描

oracle sid 扫描

nmap --script=oracle-sid-brute -p 1521-1560 192.168.137.5

oracle弱口令破解

nmap --script oracle-brute -p 1521 --script-args oracle-brute.sid=ORCL,userdb=/var/passwd,passdb=/var/passwd 192.168.137.5

如果想要了解更多的脚本内容，移步官方文档 -> https://nmap.org/nsedoc/scripts/

参考链接

END

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