Information Gathering

1. DNS Brute Force

Find sub-domains with this script. Detecting sub-domains associated with an organization's domain can reveal new targets when performing a security assessment. The discovered hosts may be virtual web hosts on a single web server or distinct hosts on IP addresses spread across the world in different data centres.

The dns-brute.nse script will find valid DNS A records by trying a list of common sub-domains and finding those that successfully resolve.

nmap -p 80 --script dns-brute.nse vulnweb.com

Starting Nmap 7.93 ( https://nmap.org ) at 2023-02-24 19:58 EST
Nmap scan report for vulnweb.com (176.28.50.165)
Host is up (0.34s latency).
rDNS record for 176.28.50.165: rs202995.rs.hosteurope.de
PORT   STATE SERVICE
80/tcp open  http

Host script results:
| dns-brute: 
|   DNS Brute-force hostnames: 
|     admin.vulnweb.com - 176.28.50.165
|     firewall.vulnweb.com - 176.28.50.165
|_    dev.vulnweb.com - 176.28.50.165

Nmap done: 1 IP address (1 host up) scanned in 28.41 seconds

2. Find Hosts on IP

Another tactic for expanding an attack surface is to find virtual hosts on an IP address that you are attempting to compromise (or assess). This can be done by using the hostmap-* scripts in the NSE collection. The hostmap-bfk.nse seems to work reasonably well providing a good starting point for your recon (IP to Host services do vary in accuracy).

nmap -p 80 --script hostmap-bfk.nse nmap.org

Starting Nmap 7.93 ( https://nmap.org ) at 2023-02-24 19:47 EST
Nmap scan report for nmap.org (173.255.243.189)
Host is up (0.19s latency).
PORT   STATE SERVICE
80/tcp open  http

Host script results:
| hostmap-bfk: 
|   hosts: 
|     www.nmap.org
|     173.255.243.189
|     seclists.org
|     sectools.org
|     svn.nmap.org
|     nmap.org
|     hb.insecure.org
|     insecure.org
|     images.insecure.org
|     189.243.255.173.in-addr.arpa
|_    www.insecure.org

Nmap done: 1 IP address (1 host up) scanned in 2.10 seconds

3. Traceroute Geolocation

Perform a traceroute to your target IP address and have geolocation data plotted for each hop along the way. Makes correlating the reverse dns names of routers in your path with locations much easier.

sudo nmap --traceroute --script traceroute-geolocation.nse -p 80 hackertarget.com

Starting Nmap 7.93 ( https://nmap.org ) at 2023-02-24 21:03 EST
Nmap scan report for hackertarget.com (178.79.163.23)
Host is up (0.31s latency).
PORT   STATE SERVICE
80/tcp open  http

Host script results:
| traceroute-geolocation: 
|   HOP  RTT     ADDRESS                                                GEOLOCATION
|   1    2.09    192.168.1.1                                            - ,- 
|   2    25.55   core-xxxxx.grapevine.net.au (203.xxx.32.20)            -27,133 Australia (Unknown)
|   3    31.61   core-xxxxx.grapevine.net.au (203.xxx.32.25)            -27,133 Australia (Unknown)
|   4    25.02   xe0-0-0-icr1.cbr2.transact.net.au (202.55.144.117)     -27,133 Australia (Unknown)
|   5    23.48   xe11-3-0.cr1.cbr2.on.ii.net (150.101.33.62)            -27,133 Australia (Unknown)
|   6    43.45   ae2.br1.syd4.on.ii.net (150.101.33.22)                 -27,133 Australia (Unknown)
|   7    175.24  te0-0-0-1.br1.lax1.on.ii.net (203.16.213.69)           -27,133 Australia (Unknown)
|   8    181.29  TenGE13-2.br02.lax04.pccwbtn.net (206.223.123.93)      38,-97 United States (Unknown)
|   9    310.46  telecity.ge9-9.br02.ldn01.pccwbtn.net (63.218.13.222)  51,0 United Kingdom (London)
|   10   309.63  212.111.33.238                                         51,0 United Kingdom (Unknown)
|_  11   338.95  hackertarget.com (178.79.163.23)                       51,0 United Kingdom (Unknown)

TRACEROUTE (using port 80/tcp)
HOP RTT       ADDRESS
1   2.09 ms   192.168.1.1
2   25.55 ms  core-xxxxx.grapevine.net.au (203.xxx.32.20)
3   31.61 ms  core-xxxxx.grapevine.net.au (203.xxx.32.25)
4   25.02 ms  xe0-0-0-icr1.cbr2.transact.net.au (202.55.144.117)
5   23.48 ms  xe11-3-0.cr1.cbr2.on.ii.net (150.101.33.62)
6   43.45 ms  ae2.br1.syd4.on.ii.net (150.101.33.22)
7   175.24 ms te0-0-0-1.br1.lax1.on.ii.net (203.16.213.69)
8   181.29 ms TenGE13-2.br02.lax04.pccwbtn.net (206.223.123.93)
9   310.46 ms telecity.ge9-9.br02.ldn01.pccwbtn.net (63.218.13.222)
10  309.63 ms 212.111.33.238
11  338.95 ms hackertarget.com (178.79.163.23)

HTTP Recon

Nmap comes with a wide range of NSE scripts for testing web servers and web applications. An advantage of using the NSE scripts for your HTTP reconnaissance is that you are able to test aspects of a web server against large subnets. This can quickly provide a picture of the types of servers and applications in use within the subnet.

4. http-enum.nse

One of the more aggressive tests, this script effectively brute forces a web server path in order to discover web applications in use. Attempts will be made to find valid paths on the web server that match a list of known paths for common web applications. The standard test includes testing of over 2000 paths, meaning that the web server log will have over 2000 entries that are HTTP 404 not found, not a stealthy testing option! This is very similar to the famous Nikto web server testing tool (that performs 6000+ tests).

nmap --script http-enum 192.168.10.55

Nmap scan report for ubuntu-test (192.168.10.55)
Host is up (0.024s latency).
Not shown: 993 closed ports
PORT     STATE SERVICE
22/tcp   open  ssh
25/tcp   open  smtp
80/tcp   open  http
| http-enum: 
|   /robots.txt: Robots file
|   /readme.html: WordPress version 3.9.2
|   /css/: Potentially interesting directory w/ listing on 'apache/2.2.22 (ubuntu)'
|   /images/: Potentially interesting directory w/ listing on 'apache/2.2.22 (ubuntu)'
|_  /js/: Potentially interesting directory w/ listing on 'apache/2.2.22 (ubuntu)'

Additional options:

Specify base path, for example you could specify a base path of /pub/.

nmap --script -http-enum --script-args http-enum.basepath='pub/' 192.168.10.55

Nmap scan report for xbmc (192.168.1.5)
Host is up (0.0012s latency).
PORT   STATE SERVICE
80/tcp open  http
| http-enum: 
|   /pub/: Root directory w/ listing on 'apache/2.2.22 (ubuntu)'
|   /pub/images/: Potentially interesting directory w/ listing on 'apache/2.2.22 (ubuntu)'
|_  /pub/js/: Potentially interesting directory w/ listing on 'apache/2.2.22 (ubuntu)'

Nmap done: 1 IP address (1 host up) scanned in 1.03 seconds

5. HTTP Title

It is not a difficult thing to find the Title of the web page from a web server, this script just makes it easier to get those title's in one set of results from a range of IP addresses.

Having the title of the page included in the Nmap scan results can provide context to a host, that may identify the primary purpose of the web server and whether that server is a potential attack target.

nmap --script http-title -sV -p 80 192.168.1.0/24

Starting Nmap 7.93 ( https://nmap.org ) at 2023-02-24 20:47 EST
Nmap scan report for 192.168.1.1
Host is up (0.0018s latency).
PORT   STATE SERVICE VERSION
80/tcp open  http    Linksys wireless-G WAP http config (Name RT-N16)
|_http-title: 401 Unauthorized
Service Info: Device: WAP

Nmap scan report for xbmc (192.168.1.115)
Host is up (0.0022s latency).
PORT   STATE SERVICE VERSION
80/tcp open  http    Apache httpd 2.2.22 ((Ubuntu))
|_http-title: Site doesn't have a title (text/html).

Nmap scan report for 192.168.1.118
Host is up (0.0035s latency).
PORT   STATE SERVICE VERSION
80/tcp open  upnp    Epson WorkForce 630 printer UPnP (UPnP 1.0; Epson UPnP SDK 1.0)
|_http-title: WorkForce 630
Service Info: Device: printer; CPE: cpe:/h:epson:workforce_630

Service detection performed. Please report any incorrect results at http://nmap.org/submit/ .
Nmap done: 256 IP addresses (8 hosts up) scanned in 10.17 seconds

Microsoft Windows Network Recon

Find operating systems, users, processes and more from systems within your local windows network with these information gathering scripts. Generally these smb-* scripts will get you a lot more information if you have valid credentials. However, with even Guest or Anonymous access you will usually be able to at least expand your knowledge of the network.

6. smb-os-discovery.nse

Determine operating system, computer name, netbios name and domain with the smb-os-discovery.nse script. An example use case could be to use this script to find all the Windows XP hosts on a large network, so they can be unplugged and thrown out (Windows XP is no longer supported by Microsoft). The key advantage to using Nmap for something like this rather than a Microsoft native tool is that it will find all systems connected to the network not just those attached to a domain.

nmap -p 445 --script smb-os-discovery 192.168.1.0/24

Starting Nmap 7.93 ( https://nmap.org ) at 2023-02-24 23:32 EST

Nmap scan report for test1 (192.168.1.115)
Host is up (0.0035s latency).
PORT    STATE SERVICE
445/tcp open  microsoft-ds

Host script results:
| smb-os-discovery: 
|   OS: Unix (Samba 3.6.3)
|   Computer name: ubuntu003
|   NetBIOS computer name: 
|   Domain name: 
|   FQDN: ubuntu003
|_  System time: 2023-02-24T23:34:41+10:00

Nmap scan report for 192.168.1.101
Host is up (0.018s latency).
PORT    STATE SERVICE
445/tcp open  microsoft-ds

Host script results:
| smb-os-discovery: 
|   OS: Windows XP (Windows 2000 LAN Manager)
|   OS CPE: cpe:/o:microsoft:windows_xp::-
|   Computer name: test-xp3
|   NetBIOS computer name: TEST-XP3
|   Workgroup: WORKGROUP
|_  System time: 2023-02-24T23:33:01+01:00

7. smb-brute.nse

Another example of the smb series of NSE scripts is the smb-brute.nse that will attempt to brute force local accounts against the SMB service.

While I would not classify brute forcing accounts as a recon function of the assessment process this script can lead to large amount of recon if we do get valid credentials as there are other smb-* scripts that can be leveraged to retrieve all local user accounts smb-enum-users.nse, groups smb-enum-groups.nse, processes smb-enum-processes.nse and even execute processes remotely with the smb-psexec.nse script.

nmap -sV -p 445 --script smb-brute 192.168.1.101

Starting Nmap 7.93 ( https://nmap.org ) at 2023-02-24 23:47 EST
Nmap scan report for 192.168.1.101
Host is up (0.060s latency).
PORT    STATE SERVICE      VERSION
445/tcp open  microsoft-ds Microsoft Windows XP microsoft-ds
Service Info: OS: Windows; CPE: cpe:/o:microsoft:windows

Host script results:
| smb-brute: 
|_  No accounts found

Service detection performed. Please report any incorrect results at http://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 115.04 seconds

As can be seen in the example above we have not found any accounts. So lets take a look at the activity on the wire while the smb-brute.nse script was running.

It is pretty clear from this Wireshark capture that sessions were being established and a large number of account credentials were being tested.

Digging deeper and finding Gold with Nmap NSE scripts

This was a quick skim of the capabilities of a sample of the Nmap NSE scripts. Time to look a bit deeper. There are literally hundreds of scripts now available and included in a regular Nmap installation. Each of the .nse files comes with documentation right there in the script or more information can be found on the NSE scripts documentation portal.

Locating NSE Scripts

To find the complete list of NSE scripts location on an Nmap installation use;

 $ locate *.nse 

or filter with area of interest such as below;

 $ locate nse | grep scripts | grep dns 

Take a look through the included scripts. There are many surprising finds, not only for recon, but also scripts for discovery of exploitable services.

  Updated: 24 February 2023

The post 7 Nmap NSE Scripts for Recon appeared first on HackerTarget.com.

The python script parses the Nmap XML output from the ssl-cert.nse script and produces csv output with the target SSL certificate details.

libssl-dev package

When compiling Nmap you need the libssl-dev package installed. Nmap nse scripts such as ssl-cert will not work without it.

Once this is installed ./configure, make, make install to install the latest version of Nmap.

apt-get install libssl-dev

Once the package is installed go ahead and install Nmap from source. Extract the source into a folder, configure and install.

Testing the SSL cert parse script

For a quick test of the SSL cert parse script I grabbed the top 25 computing sites from Alexa.

Start Nmap with the ssl-cert nse script. The -iL option loads the list 25 target host names with the -oX producing the Nmap XML results.

nmap -iL top25-tech.txt -sV -p 443 -oX nmap-results-top25 --script=ssl-cert

Python script

Once the scan has completed, the python script below can be used to parse the Nmap XML and produce the csv output. The results can be loaded into a spreadsheet, or parsed further, depending on your needs.

testuser@ubuntu:~$ python nmap-ssl-certs.py nmap-results-top25.xml
 
150.101.195.240,www.google.com,Google Inc,US,2014-05-07,2014-08-05
31.13.70.17,*.facebook.com,Facebook, Inc.,US,2014-02-28,2015-04-13
150.101.195.212,*.google.com,Google Inc,US,2014-05-07,2014-08-05
74.125.237.149,mail.google.com,Google Inc,US,2014-05-07,2014-08-05
98.139.183.24,www.yahoo.com,Yahoo Inc.,US,2014-04-09,2015-04-09
198.35.26.96,*.wikipedia.org,Wikimedia Foundation, Inc.,US,2012-10-21,2016-01-20
199.59.148.82,twitter.com,Twitter, Inc.,US,2014-04-08,2016-05-09
216.52.242.80,www.linkedin.com,LinkedIn Corporation,US,2013-12-19,2016-12-30
98.136.189.41,*.login.yahoo.com,Yahoo Inc.,US,2014-04-08,2015-04-09
65.55.143.19,mail.live.com,Microsoft Corporation,US,2013-05-21,2015-05-22
150.101.195.216,*.google.com,Google Inc,US,2014-05-07,2014-08-05
150.101.195.227,*.google.com,Google Inc,US,2014-05-07,2014-08-05
119.160.243.163,search.yahoo.com,Yahoo Inc.,US,2014-04-08,2015-04-09
192.0.82.252,wordpress.com,Automattic, Inc.,US,2014-04-16,2016-04-16
204.79.197.200,*.bing.com,Microsoft Corporation,US,2014-05-20,2016-05-19
54.225.139.43,*.pinterest.com,Pinterest Inc,US,2014-04-09,2017-04-13
66.235.120.127,,,,,
150.101.195.249,*.google.com,Google Inc,US,2014-05-07,2014-08-05
65.55.206.228,,,,,
66.211.169.66,paypal.com,PayPal, Inc.,US,2013-01-09,2015-01-11
134.170.188.221,microsoft.com,,,2013-06-20,2015-06-20
17.172.224.47,apple.com,Apple Inc.,US,2012-11-13,2014-11-03
23.23.110.81,*.imgur.com,Imgur, Inc.,US,2013-06-25,2016-08-31
198.252.206.140,*.stackexchange.com,Stack Exchange, Inc.,US,2013-07-02,2016-07-06
68.71.220.3,,,,,

The script is simple but it works. It should be pretty easy to read allowing modification to parse other NSE scripts and results from the Nmap XML output.

Parse XML data

There are many ways to parse XML data. The xml.dom method used here seems to be one of the more straightforward for parsing the Nmap XML. Another option could include using ElementTree, or even using xmlstarlet in bash as seen on this stack.exchange post.

#!/usr/bin/env python
import xml.dom.minidom
import sys
import getopt
try: 
    scandata = sys.argv[1]
except:
    print "*** You need to supply an Nmap XML file ***"
if scandata:
    doc = xml.dom.minidom.parse(scandata)
    output = []
    for host in doc.getElementsByTagName("host"):
        ip = ''
        commonName = ''
        organizationName = ''
        countryName = ''
        notBefore = ''
        notAfter = ''
        addresses = host.getElementsByTagName("address")
        ip = addresses[0].getAttribute("addr")                         # Get IP address from addr element 
        scripts = host.getElementsByTagName("script")
        for script in scripts:
              for elem in script.getElementsByTagName("elem"):         # Get cert details for each target 
                 try:
                    if elem.getAttribute("key") == 'commonName':
                       if commonName == '':                            # Only get the first commonName 
                           commonName =  elem.childNodes[0].nodeValue
                 except:
                    pass
                 try:
                    if elem.getAttribute("key") == 'organizationName':
                       if organizationName == '': 
                           organizationName =  elem.childNodes[0].nodeValue
                 except:
                    pass
                 try:
                    if elem.getAttribute("key") == 'countryName':
                       countryName =  elem.childNodes[0].nodeValue
                 except:
                    pass
                 try:
                    if elem.getAttribute("key") == 'notBefore':
                       notBefore =  elem.childNodes[0].nodeValue
                       notBefore = notBefore.split('T')[0]
                 except:
                    pass
                 try:
                    if elem.getAttribute("key") == 'notAfter':
                       notAfter =  elem.childNodes[0].nodeValue
                       notAfter = notAfter.split('T')[0]
                 except:
                    pass
        output.append(ip + ',' + commonName + ',' + organizationName + ',' + countryName + ',' + notBefore + ',' + notAfter)
    for i in output:
        print i

Nmap XML to CSV

Not specifically tied to the SSL results; we have another script that converts Nmap XML to CSV. This is an easy to use script that can be adapted to achieve the output needed for reporting.

Different organisations have different reporting requirements so this simple script was created to enable anyone to modify it as required with minimal python knowledge.

https://github.com/hackertarget/nmap-csv-xlsx

The post Parse Nmap XML to get SSL Certificate details appeared first on HackerTarget.com.

Nmap Target Selection

These are all default scans, which will scan 1000 TCP ports. Host discovery will take place.

Nmap Port Selection

Nmap Port Scan types

Privileged access is required to perform the default SYN scans. If privileges are insufficient a TCP connect scan will be used. A TCP connect requires a full TCP connection to be established and therefore is a slower scan.

Ignoring discovery is often required as many firewalls or hosts will not respond to PING. Selection option to disable Ping -Pn. This can make scan times much longer as you could end up sending scan probes to hosts that are not there.

Take a look at the Nmap Tutorial for a detailed look at the scan process.

Service and OS Detection

Service and OS detection rely on different methods to determine the operating system or service running on a particular port. The more aggressive service detection is often helpful if there are services running on unusual ports. On the other hand the lighter version of the service will be much faster as it does not really attempt to detect the service simply grabbing the banner of the open service.

Nmap Output Formats

The default format could also be saved to a file using a simple file redirect command > file. Using the -oN option allows the results to be saved but also can be monitored in the terminal as the scan is under way.

Nmap Output to CSV

Nmap by default has no csv output format. Use the XML output to extract the relevant fields into csv with python.

Jump over to github and grab our sample script that can be easily modified depending on your requirements. With csv files it is easy to convert into xlsx for reporting. This can be done manually or using our python conversion script.

Digging deeper with NSE Scripts

A search on Kali shows 609 NSE scripts. These scripts can perform a wide range of security-related testing and discovery functions. Get serious about network scanning and take the time to get familiar with some of them.

The option --script-help=$scriptname will display help for the individual scripts. To get a list of the installed scripts use locate *.nse.

The above examples use the --sV service detection flag. Generally, most NSE scripts will be more effective and will achieve better coverage by including service detection.

A scan to search for DDOS reflection UDP services

UDP based DDOS reflection attacks are a common problem that network defenders come up against. This is a handy Nmap command that will scan a target list for systems with open UDP services that allow these attacks to take place. Full details of the command and the background can be found on the Sans Institute Blog where it was first posted.

HTTP Service Information

There are many HTTP information gathering scripts, here are a few that are simple but helpful when examining larger networks. Helps in quickly identifying what the HTTP service that is running on the open port. Note the http-enum script is particularly noisy. It is similar to Nikto in that it will attempt to enumerate known paths of web applications and scripts. This will inevitably generated hundreds of 404 HTTP responses in the web server error and access logs.

Detect Heartbleed SSL Vulnerability

Heartbleed detection is one of the available SSL scripts. It will detect the presence of the well known Heartbleed vulnerability in SSL services. Specify alternative ports to test SSL on mail and other protocols (Requires Nmap 6.46).

IP Address information

Gather information related to the IP address and netblock owner of the IP address. Uses ASN, whois and geoip location lookups. See the IP Tools for more information and similar IP address and DNS lookups.

Remote Scanning

Testing your network perimeter from an external perspective is key when you wish to get the most accurate results. By assessing your exposure from the attackers perspective you can validate firewall rule audits and understand exactly what is allowed into your network.

To enable remote scanning easily and effectively use the hosted or online version of the Nmap port scanner. Because anyone who has played with shodan.io knows very well how badly people test their perimeter networks.

Additional Resources

The above commands are just a taste of the power of Nmap. Check out the following articles for more information and go further with Nmap.

To view the full set of features run Nmap with no options. The creator of Nmap, Fyodor, has a book available that covers the tool in depth.

The post Nmap Cheat Sheet appeared first on HackerTarget.com.