Zal.:.

Zal Walt

Nmap is a free utility tool for network discovery, port scanning and security auditing, even though we can use it for more than that but in this article we will learn how to do these three things with nmap.

The original author of nmap is Gordon Lyon (Fyodor). Nmap is licensed under GPL v2 and has available ports in many different languages. Nmap is available for Linux, Windows, and Mac OS X. You can download your copy of nmap from their website.

Lets get started with nmap.

When performing pentests we always look for networks we are going to attack. We need to identify live hosts on the network so that we can attack them. There are plenty of tools available for finding live hosts on a network but nmap is one of the best tools for doing this job.

Lets start with simple host (target) discovery scans i,e scans that will tell us which ip address is up on our target network. Those ip addresses which are up on our target network are the ones that are assigned to a device connected on our target network. Every device on the network is going to have a unique ip address.
To perform a simple host discovery scan we use the following command

nmap -v -sn 10.10.10.0/24

flags we used in the above command are
-v for verbose output
-sn to disable port scan (we don't want to scan for ports right now)

Following the flags is the ip address of the target network on which we want to look for live hosts. The /24 at the end of the ip address is the CIDR that specifies the subnet of the network on which we are looking for live hosts.

After running the above command you should get a list of live hosts on your target network.
If you just want to know the list of ip addresses your command is going to scan, you can use the -sL flag of the nmap like this.

nmap -sL 10.10.10.0/24

this command will simply output the list of ip addresses to scan.

We sometimes want to do dns resolution (resolving ip addresses to domain names) when performing our network scans and sometimes we don't want dns resolution. While performing a host discovery scan with nmap if we want to perform dns resolution we use -R flag in our command like this:

nmap -v -sn -R 10.10.10.0/24

And if we don't want to perform dns resolution of hosts during our scan we add the -n flag to our command like this:

nmap -v -sn -n 10.10.10.0/24

After we have discovered the hosts that are up on our target network, we usually put the ip addresses of these hosts into a file for further enumeration.

Next step in our enumeration would be to detect which operating system and which ports are running on these live hosts, for that we run this command:

nmap -O -v 10.10.10.119

here we use -O (capital o not zero) for operating system detection and by default nmap performs SYN Scan for port discovery. However nmap scans for 1000 ports only by default of a particular host.

To make nmap go over a list of ip addresses in a file we use -iL flag like this:

nmap -O -v -iL targetlist

where targetlist is the name of the file which contains ip addresses that we want to perform port scan on.

To make nmap scan all the ports of a target we use the -p flag like this:

nmap -p- -v 10.10.10.121

We can also specify a range of ports using the -p flag like this:

nmap -p1-500 -v 10.10.10.121

here 1-500 means scan all the ports from 1 to 500.

We can use a number of scan techniques to discover open ports on our network but I will only discuss some of them for brevity.

We can perform a TCP SYN scan using nmap with -sS flag like this:

nmap -sS -v 10.10.10.150

We have also flags for TCP connect and ACK scans which are -sT -sA

nmap -sT -v 10.10.10.150

nmap -sA -v 10.10.10.150

We can also perform UDP scan as well instead of TCP scan using -sU flag

nmap -sU -v 10.10.10.150

We can perform TCP Null, FIN, and Xmas scans using the flags -sN, -sF, -sX

nmap -sN -v 10.10.10.150

nmap -sF -v 10.10.10.150

nmap -sX -v 10.10.10.150

If you don't know what these scans are then please visit Port Scanning Techniques and Algorithms for explanation.

After discovering the open ports on our target host, we want to enumerate what services are running on those open ports. To enumerate services and versions information on open ports we use the -sV flag like this:

nmap -sV -v 10.10.10.118

This should give us information about what services are running on what ports and what versions of those services are running on the target host.

nmap has an interesting feature called NSE nmap scripting engine. It allows users to write their own scripts, using the Lua programming language, to automate a wide variety of networking tasks. nmap ships with a diverse set of scripts which are very helpful to enumerate a target. To use the nmap default set of scripts while enumerating the target, we use the -sC flag like this:

nmap -sC -sV -v 10.10.10.118

We can also save the results of our nmap scans to a file using the -o flag like this

nmap -sC -sV -v -oA defaultscan 10.10.10.119

here -oA tells the nmap to output results in the three major formats at once and defaultscan is the name of the file that will be prepended to all the three output files.

This is the end of this short tutorial see you next time.

References:
https://nmap.org/book/scan-methods-null-fin-xmas-scan.html

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Zal Walt

Recovering data from a backup should be an easy thing to do. At least this is what you expect. Yesterday I had a problem which should have been easy to solve, but it was not. I hope this blog post can help others who face the same problem.

The problem

1. I had an encrypted Time Machine backup which was not used for months
2. This backup was not on an official Apple Time Capsule or on a USB HDD, but on a WD MyCloud NAS
3. I needed files from this backup
4. After running out of time I only had SSH access to the macOS, no GUI

The struggle

By default, Time Machine is one of the best and easiest backup solution I have seen. As long as you stick to the default use case, where you have one active backup disk, life is pink and happy. But this was not my case.

As always, I started to Google what shall I do. One of the first options recommended that I add the backup disk to Time Machine, and it will automagically show the backup snapshots from the old backup. Instead of this, it did not show the old snapshots but started to create a new backup. Panic button has been pressed, backup canceled, back to Google.

Other tutorials recommend to click on the Time Machine icon and pressing alt (Option) key, where I can choose "Browse other backup disks". But this did not list the old Time Machine backup. It did list the backup when selecting disks in Time Machine preferences, but I already tried and failed that way.

YAT (yet another tutorial) recommended to SSH into the NAS, and browse the backup disk, as it is just a simple directory where I can see all the files. But all the files inside where just a bunch of nonsense, no real directory structure.

YAT (yet another tutorial) recommended that I can just easily browse the content of the backup from the Finder by double-clicking on the sparse bundle file. After clicking on it, I can see the disk image on the left part of the Finder, attached as a new disk.
Well, this is true, but because of some bug, when you connect to the Time Capsule, you don't see the sparse bundle file. And I got inconsistent results, for the WD NAS, double-clicking on the sparse bundle did nothing. For the Time Capsule, it did work.
At this point, I had to leave the location where the backup was present, and I only had remote SSH access. You know, if you can't solve a problem, let's complicate things by restrict yourself in solutions.

Finally, I tried to check out some data forensics blogs, and besides some expensive tools, I could find the solution.

The solution

Finally, a blog post provided the real solution - hdiutil.
The best part of hdiutil is that you can provide the read-only flag to it. This can be very awesome when it comes to forensics acquisition.

To mount any NAS via SMB:

mount_smbfs afp://<username>@<NAS_IP>/<Share_for_backup> /<mountpoint>

To mount a Time Capsule share via AFP:

mount_afp afp://any_username:password@<Time_Capsule_IP>/<Share_for_backup> /<mountpoint>

And finally this command should do the job:

hdiutil attach test.sparsebundle -readonly

It is nice that you can provide read-only parameter.

If the backup was encrypted and you don't want to provide the password in a password prompt, use the following:

printf '%s' 'CorrectHorseBatteryStaple' | hdiutil attach test.sparsebundle -stdinpass -readonly

Note: if you receive the error "resource temporarily unavailable", probably another machine is backing up to the device

And now, you can find your backup disk under /Volumes. Happy restoring!

Probably it would have been quicker to either enable the remote GUI, or to physically travel to the system and login locally, but that would spoil the fun.

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Zal Walt

There are a lot of hacking tools available over the internet but mostly we need some of them. In this blog you'll learn about hacking tools which are typically used in the world of hacking by penetration testers.

SmartWhois

SmartWhois is an information-gathering program that allows you to find all available information about an IP address, hostname, or domain, including country, state or province, city, name of the network provider, administrator, and technical support contact information. SmartWhois is a graphical version of the basic Whois program.

SocksChain

SocksChain is a tool that gives a hacker the ability to attack through a chain of proxy servers. The main purpose of doing this is to hide the hacker's real IP address and therefore minimize the chance of detection. When a hacker works through several proxy servers in series, it's much harder to locate the hacker. Tracking the attacker's IP address through the logs of several proxy servers is complex and tedious work. If one of the proxy servers' log files is lost or incomplete, the chain is broken, and the hacker's IP address remains anonymous.

NeoTrace, VisualRoute, and VisualLookout

NeoTrace, VisualRoute, and VisualLookout are all packet-tracking tools with a GUI or visual interface. They plot the path the packets travel on a map and can visually identify the locations of routers and other internet working devices. These tools operate similarly to traceroute and perform the same information gathering; however, they provide a visual representation of the results.

Visualware's eMailTrackerPro

Visualware's eMailTrackerPro ( www.emailtrackerpro.com/ ) and MailTracking ( http://mailtracking.com/ ) are tools that allow an ethical hacker to track email messages. When you use these tools to send an email, forward an email, reply to an email, or modify an email, the resulting actions and tracks of the original email are logged. The sender is notified of all actions performed on the tracked email by an automatically generated email.

IPEye

IPEye is a TCP port scanner that can do SYN, FIN, Null, and XMAS scans. It's a command line tool.
IPEye probes the ports on a target system and responds with closed, reject, drop, or open. Closed means there is a computer on the other end, but it doesn't listen at the port. Reject means a firewall is rejecting the connection to the port (sending a reset back). Drop means a firewall is dropping everything to the port, or there is no computer on the other end. Open means some kind of service is listening at the port. These responses help a hacker identify what type of system is responding.

IPSecScan

IPSecScan is a tool that can scan either a single IP address or a range of addresses looking for systems that are IPSec enabled that means the system has IPSec enabled while disabled means that it either has IPSec disabled, the compatibility issue or the configuration issue that not reveal to you that it has IPSec enabled. Indeterminable means that the scanner isn't sure if IPSec is enabled or disabled.

Icmpenum

Icmpenum uses not only ICMP Echo packets to probe networks, but also ICMP Timestamp and ICMP Information packets. Furthermore, it supports spoofing and sniffing for reply packets. Icmpenum is great for scanning networks when the firewall blocks ICMP Echo packets but fails to block Timestamp or Information packets.

SNMP Scanner

SNMP Scanner allows you to scan a range or list of hosts performing ping, DNS, and Simple Network Management Protocol (SNMP) queries. This tool helps you to find out the current information about the device of SNMP nodes in the given network.

hping2 tool

The hping2 tool is notable because it contains a host of other features besides OS fingerprinting such as TCP, User Datagram Protocol (UDP), ICMP, and raw-IP ping protocols, traceroute mode, and the ability to send files between the source and target system.

THC-Scan, PhoneSweep, and TeleSweep

THC-Scan, PhoneSweep, and TeleSweep are tools that identify phone numbers and can dial a target to make a connection with a computer modem. These tools generally work by using a predetermined list of common usernames and passwords in an attempt to gain access to the system. Most remote-access dial-in connections aren't secured with a password or use very rudimentary security.