Friday, June 12, 2020

Steghide - A Beginners Tutorial

All of us want our sensitive information to be hidden from people and for that we perform different kinds of things like hide those files or lock them using different softwares. But even though we do that, those files attractive people to itself as an object of security. Today I'm going to give you a slight introduction to what is called as Steganography. Its a practice of hiding an informational file within another file like you might have seen in movies an image has a secret message encoded in it. You can read more about Steganography from Wikipedia.

In this tutorial I'm going to use a tool called steghide, which is a simple to use Steganography tool and I'm running it on my Arch Linux. What I'm going to do is simply encode an image with a text file which contains some kind of information which I don't want other people to see. And at the end I'll show you how to decode that information back. So lets get started:

Requirements:
1. steghide
2. a text file
3. an image file

After you have installed steghide, fire up the terminal and type steghide

It will give you list of options that are available.

Now say I have a file with the name of myblogpassword.txt which contains the login password of my blog and I want to encode that file into an Image file with the name of arch.jpg so that I can hide my sensitive information from the preying eyes of my friends. In order to do that I'll type the following command in my terminal:

steghide embed -ef myblogpassword.txt -cf arch.jpg

here steghide is the name of the program
embed flag is used to specify to steghide that we want to embed one file into another file
-ef option is used to specify to steghide the name (and location, in case if its in some other directory) of the file that we want to embed inside of the another file, in our case its myblogpassword.txt
-cf option is used to specify the name (and location, in case if its in some other directory) of the file in which we want to embed our file, in our case its an image file named arch.jpg

After typing the above command and hitting enter it will prompt for a password. We can specify a password here in order to password protect our file so that when anyone tries to extract our embedded file, they'll have to supply a password in order to extract it. If you don't want to password protect it you can just simply hit enter.

Now myblogpassword.txt file is embedded inside of the image file arch.jpg. You'll see no changes in the image file except for its size. Now we can delete the plain password text file myblogpassword.txt.

In order to extract the embedded file from the cover file, I'll type following command in the terminal:

steghide extract -sf arch.jpg -xf myblogpass.txt

here steghide is again name of the program
extract flag specifies that we want to extract an embedded file from a stego file
-sf option specifies the name of the stego file or in other words the file in which we embedded another file, in our case here its the arch.jpg file
-xf option specifies the name of the file to which we want to write our embedded file, here it is myblogpass.txt
(remember you must specify the name of file with its location if its somewhere else than the current directory)

After typing the above command and hitting enter, it will prompt for a password. Supply the password if any or otherwise just simply hit enter. It will extract the embedded file to the file named myblogpass.txt. Voila! you got your file back but yes the image file still contains the embedded file.

That's it, very easy isn't it?

It was a pretty basic introduction you can look for other things like encrypting the file to be embedded before you embed it into another file and so on... enjoy :)

Osueta: A Simple Python Script To Exploit The OpenSSH User Enumeration Timing Attack

About Osueta?
Osueta it's a simple Python 2 script to exploit the OpenSSH User Enumeration Timing Attack, present in OpenSSH versions <= 7.2 and >= 5.*. The script has the ability to make variations of the username employed in the bruteforce attack, and the possibility to establish a DoS condition in the OpenSSH server.

Read more: OpenSSH User Enumeration Time-Based Attack

The bug was corrected in OpenSSH version 7.3.

Authors of Osueta:

c0r3dump3d: coredump@autistici.org
rofen: rofen@gmx.de

Osueta's Installation
For Linux users, open your Terminal and enter these commands:
If you're Windows users, follow these steps:

Install Python 2.7.x from Python.org first. On Install Python 2.7.x Setup, choose Add python.exe to Path.
Download Osueta-master zip file.
Then unzip it.
Open CMD or PowerShell window at the Osueta folder you have just unzipped and enter these commands:
pip install python-nmap paramiko IPy
python osueta.py -h

Advice: Like others offensive tools, the authors disclaims all responsibility in the use of this script.

Osueta help menu:

Osueta's examples:
A single user enumeration attempt with username variations:
python2 osueta.py -H 192.168.1.6 -p 22 -U root -d 30 -v yes

A single user enumeration attempt with no user variations a DoS attack:
python2 osueta.py -H 192.168.1.6 -p 22 -U root -d 30 -v no --dos yes

Scanning a C class network with only one user:
python2 osueta.py -H 192.168.1.0/24 -p 22 -U root -v no

Scanning a C class network with usernames from a file, delay time 15 seconds and a password of 50000 characters:
python2 osueta.py -H 192.168.1.0/24 -p 22 -L usernames.txt -v yes -d 15 -l 50

Download Osueta

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Thursday, June 11, 2020

Stegcloak - Hide Secrets With Invisible Characters In Plain Text Securely Using Passwords

StegCloak is a pure JavaScript steganography module designed in functional programming style, to hide secrets inside text by compressing and encrypting with Zero Width Characters. It can be used to safely watermark strings, invisible scripts on webpages, texts on social media or for any other covert communication. Completely invisible!. See how it works in-depth here

Features

Protect your invisible secret using passwords and HMAC integrity
Cryptographically secure by encrypting the invisible secret using AES-256-CTR.
Uses 7 Invisible characters in unicode characters that works everywhere in the web.
Including the most important ones Tweets, Gmail, Whatsapp, Telegram, Instagram, Facebook etc.
Maximum Compression to reduce the payload (LZ, Huffman).
Completely invisible, uses Zero Width Characters instead of white spaces or tabs.
Super fast! Hides the Wikipedia page-source for steganography (800 lines and 205362 characters) within a covertext of 3 words in under one second.
Written in pure functional style.
Usage - Available as an API module, a CLI and also a Web Interface (optimized with web workers).

Installing
Using npm,

$ npm install -g stegcloak

Using npm (to use it locally in your program),

$ npm install stegcloak

How it works

CLI Usage

Hide

$ stegcloak hide

Options:

  hide [options] [secret] [cover]

  -f, --file <file>       Extract input from file
  -n, --nocrypt           If you don't need encryption (default: false)
  -i, --integrity         If additional security of preventing tampering is needed (default: false)
  -o, --output <output>   Stream the results to an output file
  -h, --help              display help for command

Reveal

$ stegcloak reveal

Options:

  reveal [data]

  -f, --file <file>       Extract input from file
  -cp, --clip             Copy Data directly from clipboard
  -o, --output <output>   Stream the secret to an output file
  -h, --help              display help for command

API Usage

const StegCloak = require('stegcloak');

const stegcloak = new StegCloak(true, false);  // Initializes with encryption true and hmac false for hiding

// These arguments are used only during hide

// Can be changed later by switching boolean flags for stegcloak.encrypt and stegcloak.integrity

What's HMAC and do I need it?

HMAC is an additional fingerprint security step taken towards tampering of texts and to verify if the message received was actually sent by the intended sender. If the data is sent through WhatsApp, Messenger or any social media platform, this is already taken care of! However, if you are using StegCloak in your program to safely transmit and retrieve, this option can be enabled and StegCloak takes care of it.

Hide

stegcloak.hide(secret,password,cover) -> string

const magic = stegcloak.hide("Voldemort is back", "mischief managed", "The WiFi's not working here!");

// Uses stegcloak.encrypt and stegcloak.integrity booleans for obfuscation

console.log(magic);  // The WiFi's not working here!

Reveal

stegcloak.reveal(data, password) -> string

const secret = stegcloak.reveal(magic, "mischief managed");

// Automatically detects if encryption or integrity checks were done during hide and acts accordingly

console.log(secret); // Voldemort is back

Important

Stegcloak does'nt solve the alice-bob-warden problem, its powerful only when people are not looking for it and it helps you to achieve that really well given its invisible properties around the web! It could be safely used for watermarking in forums, invisible tweets,irc chats,social media etc. Please don't use it when you know there's someone who is actively sniffing your data looking at the unicode characters through a data analysis tool, in that case even though the secret encoded cannot be deciphered the fact lies that the warden ( Middle-man ) now knows some secret communication took place, cause he would have noticed an unusual amount of special invisible characters.

Resources
The following papers were referred to for insight and understanding of using Zero Width Characters in steganography.

Milad Taleby Ahvanooey, Qianmu Li , Jun Hou, Ahmed Raza Rajput and Chen Yini

Modern Text Hiding, Text Steganalysis, and Applications: A Comparative Analysis

Taleby Ahvanooey, Milad & Li, Qianmu & Hou, Jun & Dana Mazraeh, Hassan & Zhang, Jing.

AITSteg: An Innovative Text Steganography Technique for Hidden Transmission of Text Message via Social Media.
IEEE Access

Acknowledgements
The StegCloak logo was designed by Smashicons.

Download Stegcloak

via KitPloit