Ni Silenciosas Ni Silenciadas: mayo 2023

miércoles, 31 de mayo de 2023

How To Start | How To Become An Ethical Hacker

Are you tired of reading endless news stories about ethical hacking and not really knowing what that means? Let's change that!

This Post is for the people that:

Have No Experience With Cybersecurity (Ethical Hacking)
Have Limited Experience.
Those That Just Can't Get A Break

OK, let's dive into the post and suggest some ways that you can get ahead in Cybersecurity.

I receive many messages on how to become a hacker. "I'm a beginner in hacking, how should I start?" or "I want to be able to hack my friend's Facebook account" are some of the more frequent queries. Hacking is a skill. And you must remember that if you want to learn hacking solely for the fun of hacking into your friend's Facebook account or email, things will not work out for you. You should decide to learn hacking because of your fascination for technology and your desire to be an expert in computer systems. Its time to change the color of your hat 😀

I've had my good share of Hats. Black, white or sometimes a blackish shade of grey. The darker it gets, the more fun you have.

If you have no experience don't worry. We ALL had to start somewhere, and we ALL needed help to get where we are today. No one is an island and no one is born with all the necessary skills. Period.OK, so you have zero experience and limited skills…my advice in this instance is that you teach yourself some absolute fundamentals.

Let's get this party started.

What is hacking?

Hacking is identifying weakness and vulnerabilities of some system and gaining access with it.

Hacker gets unauthorized access by targeting system while ethical hacker have an official permission in a lawful and legitimate manner to assess the security posture of a target system(s)

There's some types of hackers, a bit of "terminology".
White hat — ethical hacker.
Black hat — classical hacker, get unauthorized access.
Grey hat — person who gets unauthorized access but reveals the weaknesses to the company.
Script kiddie — person with no technical skills just used pre-made tools.
Hacktivist — person who hacks for some idea and leaves some messages. For example strike against copyright.

Skills required to become ethical hacker.

Curosity anf exploration
Operating System
Fundamentals of Networking

*Note this sites

More info

inBINcible Writeup - Golang Binary Reversing

This file is an 32bits elf binary, compiled from go language (i guess ... coded by @nibble_ds ;)

The binary has some debugging symbols, which is very helpful to locate the functions and api calls.

GO source functions:

- main.main

- main.function.001

If the binary is executed with no params, it prints "Nope!", the bad guy message.

~/ncn$ ./inbincible

Nope!

Decompiling the main.main function I saw two things:

1. The Argument validation: Only one 16 bytes long argument is needed, otherwise the execution is finished.

2. The key IF, the decision to dexor and print byte by byte the "Nope!" string OR dexor and print "Yeah!"

The incoming channel will determine the final message.

Dexor and print each byte of the "Nope!" message.

This IF, checks 16 times if the go channel reception value is 0x01, in this case the app show the "Yeah!" message.

Go channels are a kind of thread-safe queue, a channel_send is like a push, and channel_receive is like a pop.

If we fake this IF the 16 times, we got the "Yeah!" message:

(gdb) b *0x8049118
(gdb) commands
>set {char *}0xf7edeef3 = 0x01
>c
>end

(gdb) r 1234567890123456
tarting program: /home/sha0/ncn/inbincible 1234567890123456
...
Yeah!

Ok, but the problem is not in main.main, is main.function.001 who must sent the 0x01 via channel.

This function xors byte by byte the input "1234567890123456" with a byte array xor key, and is compared with another byte array.

=> 0x8049456: xor %ebp,%ecx

This xor, encode the argument with a key byte by byte

The xor key can be dumped from memory but I prefer to use this macro:

(gdb) b *0x8049456
(gdb) commands
>i r ecx
>c
>end
(gdb) c

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x12 18

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x45 69

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x33 51

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x87 135

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x65 101

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x12 18

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x45 69

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x33 51

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x87 135

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x65 101

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x12 18

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x45 69

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x33 51

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x87 135

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x65 101

Breakpoint 2, 0x08049456 in main.func ()
ecx 0x12 18

The result of the xor will compared with another array byte, each byte matched, a 0x01 will be sent.

The cmp of the xored argument byte,
will determine if the channel send 0 or 1

(gdb) b *0x0804946a
(gdb) commands
>i r al
>c
>end

At this point we have the byte array used to xor the argument, and the byte array to be compared with, if we provide an input that xored with the first byte array gets the second byte array, the code will send 0x01 by the channel the 16 times.

Now web have:

xorKey=[0x12,0x45,0x33,0x87,0x65,0x12,0x45,0x33,0x87,0x65,0x12,0x45,0x33,0x87,0x65,0x12]

mustGive=[0x55,0x75,0x44,0xb6,0x0b,0x33,0x06,0x03,0xe9,0x02,0x60,0x71,0x47,0xb2,0x44,0x33]

Xor is reversible, then we can get the input needed to dexor to the expected values in order to send 0x1 bytes through the go channel.

>>> x=''
>>> for i in range(len(xorKey)):
... x+= chr(xorKey[i] ^ mustGive[i])
...
>>> print x

G0w1n!C0ngr4t5!!

And that's the key :) let's try it:

~/ncn$ ./inbincible 'G0w1n!C0ngr4t5!!'
Yeah!

Got it!! thanx @nibble_ds for this funny crackme, programmed in the great go language. I'm also a golang lover.

Continue reading

5 Free Online Courses To Learn Artificial Intelligence

We are living in the era of fourth industrial revolution(4IR), where Artificial intelligence has a significant role to play. This 4IR technology embedded within societies and even into the human body. From Computer enthusiasts to common people, everyone should be aware and learn this breakthrough technology.

We think about gigantic Robots from Transformers when we hear about Artificial Intelligence(AI) which is a fiction in the past but a fact today, capable of transforming the whole tech world. The field of AI consists of more than Robots such as personal assistants, self-driving cars, apprenticeship learning, behavior cloning and so on. To learn about this advanced technology, thanks to the online learning resources which offers great content to get started with artificial intelligence.

Here are the 5 free e-learning courses on Artificial Intelligence

1. UC Berkeley CS188 Intro to AI

Get started with UC Berkeley AI course, this course is absolutely for beginners who are unaware of Artificial intelligence. It doesn't need any prior computer knowledge to know about AI. UC Berkeley allows anyone to learn this course for free. This course is systematically presented and consists of the following:

Course Schedule
Complete sets of Lecture Slides and Videos
Interface for Electronic Homework Assignments
Section Handouts
Specs for the Pacman Projects
Source files and PDFs of past Berkeley CS188 exams
Form to apply for edX hosted autograders for homework and projects (and more)
Contact information

Aside from this, you can also browse the following courses as well from UC Berkeley that are part of AI course:

Machine Learning: CS189, Stat154
Intro to Data Science: CS194-16
Probability: EE126, Stat134
Optimization: EE127
Cognitive Modeling: CogSci131
Machine Learning Theory: CS281A, CS281B
Vision: CS280
Robotics: CS287
Natural Language Processing: CS288

2. Artificial Intelligence: Principles and Techniques

This course is offered by Stanford with great content that includes topics, videos, assignments, projects, and exams. The whole course mainly focuses on the complex real-world problems and try to find similarity between web search, speech recognition, face recognition, machine translation, autonomous driving, and automatic scheduling. Here you will learn the foundational principles of AI and implement some the AI systems. The goal of this course is to help you tackle the real-world situations with the help of AI tools. So, it is the best for the beginner to get started with AI.

3. Learn with GOOGLE AI

Who will dislike the course from Google? absolutely no one. This company is one of the early adopters of AI has a lot to offer to learners. Learn with Google AI is an education platform for people at all experience levels, it is free to access and browse content. The education resources provided by Google is from the machine learning experts of the company. These resources are the collections of lessons, tutorials, and Hands-on exercises that help you start learning, building, and problem-solving.

4. MIT 6.S094: Deep Learning for Self-Driving Cars

This course gives the practical overview of Deep Learning and AI. It is the course for beginners, also for the people who are getting started with Machine Learning. The course also offers a lot of benefits to the experienced and advanced researchers in the field deep learning. This MIT's course takes people into the journey of Deep Learning with the applied theme of building Self-Driving cars. However, the course also offers slides and videos to engage the learners.

5. Fundamentals of Deep Learning for Computer Vision

This course is offered by Nvidia and Nvidia Deep learning Institute. Computer Vision is one of the disciplines of AI that acquire, analyze, process, and understand images. The course is completely free and everyone who is enthusiast about AI can access and learn the course. It is a hands-on course that able to provide basics of deep learning and deployment of neural networks. With this. you will also learn the following:

Identify the ingredients required to start a Deep Learning project.
Train a deep neural network to correctly classify images it has never seen before.
Deploy deep neural networks into applications.
Identify techniques for improving the performance of deep learning applications.
Assess the types of problems that are candidates for deep learning.
Modify neural networks to change their behavior.

martes, 30 de mayo de 2023

WiFi Hacking On Tablets

Disclaimer: Don't hack anything where you don't have the authorization to do so. Stay legal.

Ever since I bought my first Android device, I wanted to use the device for WEP cracking. Not because I need it, but I want it :) After some googling, I read that you can't use your WiFi chipset for packet injection, and I forgot the whole topic.

After a while, I read about hacking on tablets (this was around a year ago), and my first opinion was:

"This is stupid, lame, and the usage of that can be very limited".

After playing one day with it, my opinion just changed:

"This is stupid, lame, the usage is limited, but when it works, it is really funny :-)"

At the beginning I looked at the Pwn Pad as a device that can replace a pentest workstation, working at the attacker side. Boy was I wrong. Pwn Pad should be used as a pentest device deployed at the victim's side!

You have the following options:

You have 1095 USD + VAT + shipping to buy this Pwn Pad
You have around 200 USD to buy an old Nexus 7 tablet, a USB OTG cable, a USB WiFi dongle (e.g. TP-Link Wireless TL-WN722N USB adapter works).

In my example, I bought a used, old 2012 Nexus WiFi. Originally I bought this to play with different custom Android ROMs, and play with rooted applications. After a while, I found this Pwn Pad hype again and gave it a shot.

The Pwn Pad community edition has an easy-to-use installer, with a proper installation description. Don't forget to backup everything from your tablet before installing Pwn Pad on it!

I don't want to repeat the install guide, it is as easy as ABC. I booted a Ubuntu Live CD, installed adb and fastboot, and it was ready-to-roll. I have not measured the time, but the whole process was around 20 minutes.

The internal WiFi chipset can be used to sniff traffic or even ARP poisoning for active MiTM. But in my case, I was not able to use the internal chipset for packet injection, which means you can't use it for WEP cracking, WPA disauth, etc. This is where the external USB WiFi comes handy. And this is why we need the Pwn Pad Android ROM, and can't use an average ROM.

There are two things where Pwn Pad really rocks. The first one is the integrated drivers for the external WiFi with monitor mode and packet injection capabilities. The second cool thing is the chroot wrapper around the Linux hacking tools. Every hacking tool has a start icon, so it feels like it is a native Android application, although it is running in a chroot Kali environment.

Wifite

The first recommended app is Wifite. Think of it as a wrapper around the aircrack - airmon - airodump suite. My biggest problem with WEP cracking was that I had to remember a bunch of commands, or have the WEP cracking manual with me every time I have to crack it. It was overcomplicated. But thanks to Wifite, that is past.

In order to crack a WEP key, you have to:

Start the Wifite app
Choose your adapter (the USB WiFi)
Choose the target network (wep_lan in the next example)
Wait for a minute
PROFIT!

SSH reverse shell

This is one of the key functionalities of the Pwn Pad. You deploy the tablet at the Victim side, and let the tablet connect to your server via (tunneled) SSH.

The basic concept of the reverse shells are that an SSH tunnel is established between the Pwn Pad tablet (client) and your external SSH server (either directly or encapsulated in other tunneling protocol), and remote port forward is set up, which means on your SSH server you connect to a localport which is forwarded to the Pwn Pad and handled by the Pwn Pad SSH server.

I believe the best option would be to use the reverse shell over 3G, and let the tablet connect to the victim network through Ethernet or WiFi. But your preference might vary. The steps for reverse shells are again well documented in the documentation, except that by default you also have to start the SSH server on the Pwn Pad. It is not hard, there is an app for that ;-) On your external SSH server you might need to install stunnel and ptunnel if you are not using Kali. The following output shows what you can see on your external SSH server after successful reverse shell.

root@myserver:/home/ubuntu# ssh -p 3333 pwnie@localhost The authenticity of host '[localhost]:3333 ([127.0.0.1]:3333)' can't be established. ECDSA key fingerprint is 14:d4:67:04:90:30:18:a4:7a:f6:82:04:e0:3c:c6:dc. Are you sure you want to continue connecting (yes/no)? yes Warning: Permanently added '[localhost]:3333' (ECDSA) to the list of known hosts. pwnie@localhost's password:   _____      ___  _ ___ ___   _____  _____ ___ ___ ___ ___  | _ \ \    / / \| |_ _| __| | __\ \/ / _ \ _ \ __/ __/ __|  |  _/\ \/\/ /| .` || || _|  | _| >  <|  _/   / _|\__ \__ \  |_|   \_/\_/ |_|\_|___|___| |___/_/\_\_| |_|_\___|___/___/   Release Version: 1.5.5  Release Date: 2014-01-30  Copyright 2014 Pwnie Express. All rights reserved.   By using this product you agree to the terms of the Rapid Focus  Security EULA: http://pwnieexpress.com/pdfs/RFSEULA.pdf   This product contains both open source and proprietary software.  Proprietary software is distributed under the terms of the EULA.  Open source software is distributed under the GNU GPL:  http://www.gnu.org/licenses/gpl.html  pwnie@localhost:~$

Now you have a shell on a machine that is connected to the victim network. Sweet :) Now Metasploit really makes sense on the tablet, and all other command-line tools.

EvilAP and DSniff

Start EvilAP (it is again a wrapper around airobase), choose interface (for me the Internal Nexus Wifi worked), enter an SSID (e.g freewifi), enter channel, choose whether force all clients to connect to you or just those who really want to connect to you, and start.

The next step is to start DSniff, choose interface at0, and wait :) In this example, I used a popular Hungarian webmail, which has a checkbox option for "secure" login (with default off). There are sooo many problems with this approach, e.g. you can't check the certificate before connecting, and the login page is delivered over HTTP, so one can disable the secure login checkbox seamlessly in the background, etc. In this case, I left the "secure" option on default off.

In the next tutorial, I'm going to show my next favorite app, DSploit ;)

Lessons learned

Hacking has been never so easy before
In a home environment, only use WPA2 PSK
Choose a long, nondictionary passphrase as the password for WPA2
Don't share your WiFi passwords with people you don't trust, or change it when they don't need it anymore
Don't let your client device auto-connect to WiFi stations, even if the SSID looks familiar

I believe during an engagement a Pwn Plug has better "physical cloaking" possibilities, but playing with the Pwn Pad Community Edition really gave me fun moments.

And last but not least I would like to thank to the Pwn Pad developers for releasing the Community Edition!

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